diff --git a/addons/account/static/src/xml/account_dashboard_setup_bar.xml b/addons/account/static/src/xml/account_dashboard_setup_bar.xml
index 47f5b580c41..44317822c92 100644
--- a/addons/account/static/src/xml/account_dashboard_setup_bar.xml
+++ b/addons/account/static/src/xml/account_dashboard_setup_bar.xml
@@ -5,22 +5,22 @@
         <div class="o_account_dashboard_header d-none d-md-block o_form_view" t-if="values['show_setup_bar']">
             <div class="o_form_statusbar">
                 <div class="o_statusbar_status" data-original-title="" title="" >
-                    <button name="setting_chart_of_accounts_action" type="company_object" t-attf-class="btn btn-sm o_arrow_button btn-default account_setup_dashboard_action #{values['chart_of_accounts'] and 'o_action_done' or ''}" >
+                    <button name="setting_chart_of_accounts_action" type="company_object" t-attf-class="btn o_arrow_button btn-default account_setup_dashboard_action #{values['chart_of_accounts'] and 'o_action_done' or ''}" >
                         <i class="fa fa-check" t-if="values['chart_of_accounts']" role="img" aria-label="Current state" title="Current state" aria-current="step"/>
                         <b class="o_account_dashboard_index">4</b>
                         Chart of Accounts
                     </button>
-                    <button name="setting_init_fiscal_year_action" type="company_object" t-attf-class="btn btn-sm o_arrow_button btn-default account_setup_dashboard_action #{values['fiscal_year'] and 'o_action_done' or ''}">
+                    <button name="setting_init_fiscal_year_action" type="company_object" t-attf-class="btn o_arrow_button btn-default account_setup_dashboard_action #{values['fiscal_year'] and 'o_action_done' or ''}">
                         <i class="fa fa-check" t-if="values['fiscal_year']" role="img" aria-label="Current state" title="Current state" aria-current="step"/>
                         <b class="o_account_dashboard_index">3</b>
                         Fiscal Year
                     </button>
-                    <button name="setting_init_bank_account_action" type="company_object" t-attf-class="btn btn-sm o_arrow_button btn-default account_setup_dashboard_action #{values['bank'] and 'o_action_done' or ''}">
+                    <button name="setting_init_bank_account_action" type="company_object" t-attf-class="btn o_arrow_button btn-default account_setup_dashboard_action #{values['bank'] and 'o_action_done' or ''}">
                         <i class="fa fa-check" t-if="values['bank']" role="img" aria-label="Current state" title="Current state" aria-current="step"/>
                         <b class="o_account_dashboard_index">2</b>
                         Add a Bank Account
                     </button>
-                    <button name="setting_init_company_action" type="company_object" t-attf-class="btn btn-sm o_arrow_button btn-default account_setup_dashboard_action #{values['company'] and 'o_action_done' or ''}">
+                    <button name="setting_init_company_action" type="company_object" t-attf-class="btn o_arrow_button btn-default account_setup_dashboard_action #{values['company'] and 'o_action_done' or ''}">
                         <i class="fa fa-check" t-if="values['company']" role="img" aria-label="Current state" title="Current state" aria-current="step"/>
                         <b class="o_account_dashboard_index">1</b>
                         Company Data
diff --git a/addons/account/static/src/xml/account_reconciliation.xml b/addons/account/static/src/xml/account_reconciliation.xml
index d5c77c19b9e..76ad700c0af 100644
--- a/addons/account/static/src/xml/account_reconciliation.xml
+++ b/addons/account/static/src/xml/account_reconciliation.xml
@@ -59,10 +59,10 @@
     <t t-if="context &amp;&amp; context.active_model">
         <p t-if="context['active_model'] === 'account.journal' || context['active_model'] === 'account.bank.statement'" class="actions_buttons">
             <t t-if="context.journal_id">
-                <button class="button_back_to_statement btn btn-default btn-sm" t-att-data_journal_id='context.journal_id'>Go to bank statement(s)</button>
+                <button class="button_back_to_statement btn btn-default" t-att-data_journal_id='context.journal_id'>Go to bank statement(s)</button>
             </t>
             <t t-if="context['active_model'] === 'account.bank.statement'">
-                <button class="button_close_statement btn btn-primary btn-sm" style="display: inline-block;">Close statement</button>
+                <button class="button_close_statement btn btn-primary" style="display: inline-block;">Close statement</button>
             </t>
         </p>
     </t>
@@ -74,8 +74,8 @@
         <table class="accounting_view">
             <caption>
                 <div class="pull-right o_buttons">
-                    <button t-attf-class="o_validate btn btn-default btn-sm #{!state.balance.type ? '' : 'd-none'}">Validate</button>
-                    <button t-attf-class="o_reconcile btn btn-primary btn-sm #{state.balance.type &gt; 0 ? '' : 'd-none'}">Reconcile</button>
+                    <button t-attf-class="o_validate btn btn-default #{!state.balance.type ? '' : 'd-none'}">Validate</button>
+                    <button t-attf-class="o_reconcile btn btn-primary #{state.balance.type &gt; 0 ? '' : 'd-none'}">Reconcile</button>
                     <span t-attf-class="o_no_valid text-danger #{state.balance.type &lt; 0 ? '' : 'd-none'}">Select a partner or choose a counterpart</span>
                 </div>
             </caption>
@@ -107,9 +107,9 @@
 <t t-name="reconciliation.manual.line" t-extend="reconciliation.line">
     <t t-jquery=".o_buttons" t-operation="replace">
         <div class="pull-right o_buttons">
-            <button t-attf-class="o_validate btn btn-default btn-sm #{!state.balance.type ? '' : 'd-none'}">Reconcile</button>
-            <button t-attf-class="o_reconcile btn btn-primary btn-sm #{state.balance.type &gt; 0 ? '' : 'd-none'}">Reconcile</button>
-            <button t-attf-class="o_no_valid btn btn-default btn-sm #{state.balance.type &lt; 0 ? '' : 'd-none'}">Skip</button>
+            <button t-attf-class="o_validate btn btn-default #{!state.balance.type ? '' : 'd-none'}">Reconcile</button>
+            <button t-attf-class="o_reconcile btn btn-primary #{state.balance.type &gt; 0 ? '' : 'd-none'}">Reconcile</button>
+            <button t-attf-class="o_no_valid btn btn-default #{state.balance.type &lt; 0 ? '' : 'd-none'}">Skip</button>
         </div>
     </t>
     <t t-jquery=".accounting_view tbody" t-operation="append">
@@ -156,7 +156,7 @@
 
 <div t-name="reconciliation.line.create">
     <div class="quick_add">
-        <div class="btn-group btn-group-sm o_reconcile_models" t-if="state.reconcileModels">
+        <div class="btn-group o_reconcile_models" t-if="state.reconcileModels">
             <t t-foreach="state.reconcileModels" t-as="reconcileModel">
                 <button class="btn btn-primary" t-att-data-reconcile-model-id="reconcileModel.id"><t t-esc="reconcileModel.name"/></button>
             </t>
diff --git a/addons/account/views/account_journal_dashboard_view.xml b/addons/account/views/account_journal_dashboard_view.xml
index d56d51cb2b4..7e8d1b10a54 100644
--- a/addons/account/views/account_journal_dashboard_view.xml
+++ b/addons/account/views/account_journal_dashboard_view.xml
@@ -22,7 +22,7 @@
                                     <t t-if="journal_type == 'sale' || journal_type == 'purchase'" t-call="JournalBodySalePurchase"/>
                                     <t t-if="journal_type == 'general' || journal_type == 'situation'">
                                         <div class="col-xs-6 o_kanban_primary_left">
-                                            <button type="object" name="open_action" context="{'action_name': 'action_move_journal_line', 'view_no_maturity': 1}" class="btn btn-primary btn-sm">
+                                            <button type="object" name="open_action" context="{'action_name': 'action_move_journal_line', 'view_no_maturity': 1}" class="btn btn-primary">
                                                 <span>Journal Entries</span>
                                             </button>
                                         </div>
@@ -221,11 +221,11 @@
                             - If there are statements to reconcile, a link to reconcile them -->
                         <div class="col-xs-5 o_kanban_primary_left">
                             <t t-if="dashboard.number_to_reconcile > 0">
-                                <button type="object" name="action_open_reconcile" class="btn btn-primary btn-sm"> Reconcile <t t-esc="dashboard.number_to_reconcile"/> Items</button>
+                                <button type="object" name="action_open_reconcile" class="btn btn-primary"> Reconcile <t t-esc="dashboard.number_to_reconcile"/> Items</button>
                             </t>
                             <t t-if="journal_type == 'bank'">
                                 <div name="bank_journal_cta">
-                                    <button t-if="dashboard.bank_statements_source == 'undefined'" name="action_configure_bank_journal" type="object" class="btn btn-primary btn-sm">Configure</button>
+                                    <button t-if="dashboard.bank_statements_source == 'undefined'" name="action_configure_bank_journal" type="object" class="btn btn-primary">Configure</button>
                                     <div name="bank_statement_create_button" t-if="dashboard.bank_statements_source != 'online_sync'">
                                         <a type="object" name="create_bank_statement" class="oe_inline">Create</a><span name="button_import_placeholder"/> Statements
                                     </div>
@@ -235,7 +235,7 @@
                                 <a t-if="journal_type == 'cash'" type="object" name="create_cash_statement" class="oe_inline">New Transactions</a>
                             </t>
                             <t t-if="dashboard.number_to_reconcile == 0">
-                                <button t-if="journal_type == 'cash'" type="object" name="create_cash_statement" class="btn btn-primary btn-sm">New Transactions</button>
+                                <button t-if="journal_type == 'cash'" type="object" name="create_cash_statement" class="btn btn-primary">New Transactions</button>
                             </t>
                         </div>
                         <!-- On the right, show other common informations/actions -->
@@ -263,12 +263,12 @@
                     <t t-name="JournalBodySalePurchase" id="account.JournalBodySalePurchase">
                         <div class="col-xs-5 o_kanban_primary_left">
                             <t t-if="journal_type == 'sale'">
-                                <button type="object" name="action_create_new" class="btn btn-primary btn-sm o_invoice_new">
+                                <button type="object" name="action_create_new" class="btn btn-primary o_invoice_new">
                                     <span>New Invoice</span>
                                 </button>
                             </t>
                             <t t-if="journal_type == 'purchase'">
-                                <button type="object" name="action_create_new" class="btn btn-primary btn-sm">
+                                <button type="object" name="action_create_new" class="btn btn-primary">
                                     <span>New Bill</span>
                                 </button>
                             </t>
diff --git a/addons/account/views/account_portal_templates.xml b/addons/account/views/account_portal_templates.xml
index 93a1bb91e8a..1d6640c7dba 100644
--- a/addons/account/views/account_portal_templates.xml
+++ b/addons/account/views/account_portal_templates.xml
@@ -85,8 +85,8 @@
                         </div>
                         <div class="o_payment_button">
                             <div class="text-center mb8 ml16 mr16 o_download_pdf">
-                                <a class="btn btn-default btn-block btn-sm o_download_btn" t-att-href="'/my/invoices/pdf/%s?%s' % (invoice.id, keep_query())" title="Download"><i class="fa fa-download"/> Download</a>
-                                <a class="btn btn-default btn-block btn-sm d-none d-lg-inline-block o_print_btn o_portal_invoice_print" t-att-href="'/my/invoices/pdf/%s?%s&amp;print=true' % (invoice.id, keep_query())" id="print_invoice_report" title="Print"><i class="fa fa-print"/> Print</a>
+                                <a class="btn btn-default btn-block o_download_btn" t-att-href="'/my/invoices/pdf/%s?%s' % (invoice.id, keep_query())" title="Download"><i class="fa fa-download"/> Download</a>
+                                <a class="btn btn-default btn-block d-none d-lg-inline-block o_print_btn o_portal_invoice_print" t-att-href="'/my/invoices/pdf/%s?%s&amp;print=true' % (invoice.id, keep_query())" id="print_invoice_report" title="Print"><i class="fa fa-print"/> Print</a>
                             </div>
                         </div>
                         <hr t-if="invoice.user_id" class="mt0 mb0"/>
diff --git a/addons/account/views/account_view.xml b/addons/account/views/account_view.xml
index 3729b6f464b..96a4a3b3d44 100644
--- a/addons/account/views/account_view.xml
+++ b/addons/account/views/account_view.xml
@@ -345,7 +345,7 @@
                                             </div>
                                         </div>
                                         <div class="content-group" attrs="{'invisible': [('alias_domain', '!=', False)]}">
-                                            <a type='action' name='%(action_open_settings)d' class="btn btn-sm btn-link" role="button"><i class="fa fa-fw o_button_icon fa-arrow-right"/> Configure Email Servers</a>
+                                            <a type='action' name='%(action_open_settings)d' class="btn btn-link" role="button"><i class="fa fa-fw o_button_icon fa-arrow-right"/> Configure Email Servers</a>
                                     </div>
                                     </group>
                                 </group>
diff --git a/addons/account_asset/static/src/js/account_asset.js b/addons/account_asset/static/src/js/account_asset.js
index 1a403adbb6a..553cb4b73b3 100644
--- a/addons/account_asset/static/src/js/account_asset.js
+++ b/addons/account_asset/static/src/js/account_asset.js
@@ -58,7 +58,7 @@ var AccountAssetWidget = AbstractField.extend({
             type: 'button',
             title: title,
             disabled: disabled,
-        }).addClass('btn btn-sm btn-link fa fa-circle o_deprec_lines_toggler ' + className);
+        }).addClass('btn btn-link fa fa-circle o_deprec_lines_toggler ' + className);
         this.$el.html($button);
     },
 
diff --git a/addons/base_import/static/src/xml/base_import.xml b/addons/base_import/static/src/xml/base_import.xml
index 95b54b5a5af..d84800eca01 100644
--- a/addons/base_import/static/src/xml/base_import.xml
+++ b/addons/base_import/static/src/xml/base_import.xml
@@ -93,11 +93,11 @@
     </t>
 
     <t t-name="ImportView.buttons">
-        <button type="button" class="btn btn-sm btn-primary o_import_import d-none">Import</button>
-        <button type="button" class="btn btn-sm btn-default o_import_validate d-none">Test Import</button>
-        <button type="button" class="btn btn-sm btn-primary oe_import_file">Load File</button>
-        <button type="button" class="btn btn-sm btn-default o_import_file_reload d-none">Reload File</button>
-        <button type="button" class="btn btn-sm btn-default o_import_cancel">Cancel</button>
+        <button type="button" class="btn btn-primary o_import_import d-none">Import</button>
+        <button type="button" class="btn btn-default o_import_validate d-none">Test Import</button>
+        <button type="button" class="btn btn-primary oe_import_file">Load File</button>
+        <button type="button" class="btn btn-default o_import_file_reload d-none">Reload File</button>
+        <button type="button" class="btn btn-default o_import_cancel">Cancel</button>
     </t>
 
     <t t-name="ImportView.preview">
@@ -155,7 +155,7 @@
         <t t-if="error.moreinfo" t-raw="info(error.moreinfo)"/>
     </t>
     <t t-name="ImportView.import_button">
-        <button t-if='widget and widget.importEnabled' type="button" class="btn btn-sm btn-default o_button_import">
+        <button t-if='widget and widget.importEnabled' type="button" class="btn btn-default o_button_import">
             Import
         </button>
     </t>
diff --git a/addons/board/static/src/xml/board.xml b/addons/board/static/src/xml/board.xml
index d06d0872c8a..00e94d73162 100644
--- a/addons/board/static/src/xml/board.xml
+++ b/addons/board/static/src/xml/board.xml
@@ -82,7 +82,7 @@
         <input class="o_add_to_dashboard_input" type="text"/>
     </li>
     <li class="o_add_to_dashboard">
-        <button type="button" class="btn btn-primary btn-sm o_add_to_dashboard_button">Add</button>
+        <button type="button" class="btn btn-primary o_add_to_dashboard_button">Add</button>
     </li>
 </t>
 </template>
diff --git a/addons/calendar/static/src/xml/base_calendar.xml b/addons/calendar/static/src/xml/base_calendar.xml
index 0bb242ef530..26b66481b6e 100644
--- a/addons/calendar/static/src/xml/base_calendar.xml
+++ b/addons/calendar/static/src/xml/base_calendar.xml
@@ -14,9 +14,9 @@
         </t>
         <t t-jquery=".o_notification_content" t-operation="append">
             <br/><br/>
-            <button type="button" class="btn btn-sm btn-primary link2showed oe_highlight oe_form oe_button"><span>OK</span></button>
-            <button type="button" class="btn btn-sm btn-link link2event">Details</button>
-            <button type="button" class="btn btn-sm btn-link link2recall">Snooze</button>
+            <button type="button" class="btn btn-primary link2showed oe_highlight oe_form oe_button"><span>OK</span></button>
+            <button type="button" class="btn btn-link link2event">Details</button>
+            <button type="button" class="btn btn-link link2recall">Snooze</button>
         </t>
     </t>
 
diff --git a/addons/crm/wizard/crm_lead_lost_views.xml b/addons/crm/wizard/crm_lead_lost_views.xml
index 844e5e91d5f..9886c030829 100644
--- a/addons/crm/wizard/crm_lead_lost_views.xml
+++ b/addons/crm/wizard/crm_lead_lost_views.xml
@@ -9,13 +9,13 @@
                         <field name="lost_reason_id"/>
                     </group>
                     <footer>
-                        <button name="action_lost_reason_apply" string="Submit" type="object" class="btn btn-sm btn-primary"/>
-                        <button string="Cancel" class="btn btn-sm btn-default" special="cancel"/>
+                        <button name="action_lost_reason_apply" string="Submit" type="object" class="btn-primary"/>
+                        <button string="Cancel" class="btn-default" special="cancel"/>
                     </footer>
                 </form>
             </field>
         </record>
- 
+
         <record id="crm_lead_lost_action" model="ir.actions.act_window">
             <field name="name">Lost Reason</field>
             <field name="type">ir.actions.act_window</field>
diff --git a/addons/delivery/wizard/choose_delivery_package_views.xml b/addons/delivery/wizard/choose_delivery_package_views.xml
index e00afa170fa..e7c2c975ad1 100644
--- a/addons/delivery/wizard/choose_delivery_package_views.xml
+++ b/addons/delivery/wizard/choose_delivery_package_views.xml
@@ -15,8 +15,8 @@
                     </div>
                 </group>
                 <footer>
-                    <button name="put_in_pack" type="object" string="Save" class="btn btn-sm btn-primary"/>
-                    <button string="Discard" special="cancel" class="btn btn-sm btn-default"/>
+                    <button name="put_in_pack" type="object" string="Save" class="btn-primary"/>
+                    <button string="Discard" special="cancel" class="btn-default"/>
                 </footer>
             </form>
         </field>
diff --git a/addons/gamification/views/badge.xml b/addons/gamification/views/badge.xml
index 10ef3a61605..69c08fb5f68 100644
--- a/addons/gamification/views/badge.xml
+++ b/addons/gamification/views/badge.xml
@@ -137,7 +137,7 @@
                                     </div>
                                 </div>
                                 <div t-if="record.remaining_sending.value != 0" class="o_kanban_button">
-                                    <button type="action" name="%(action_grant_wizard)d" class="oe_highlight btn btn-sm btn-primary">Grant</button>
+                                    <button type="action" name="%(action_grant_wizard)d" class="oe_highlight btn btn-primary">Grant</button>
                                 </div>
                             </div>
                         </div>
diff --git a/addons/google_calendar/static/src/js/google_calendar.js b/addons/google_calendar/static/src/js/google_calendar.js
index dbb7a308540..91d3c6709b0 100644
--- a/addons/google_calendar/static/src/js/google_calendar.js
+++ b/addons/google_calendar/static/src/js/google_calendar.js
@@ -115,7 +115,7 @@ CalendarRenderer.include({
         this.$googleButton = $();
         if (this.model === "calendar.event") {
             this.$googleButton = $('<button/>', {type: 'button', html: _t("Sync with <b>Google</b>")})
-                                .addClass('o_google_sync_button oe_button btn btn-sm btn-default')
+                                .addClass('o_google_sync_button oe_button btn btn-default')
                                 .prepend($('<img/>', {
                                     src: "/google_calendar/static/src/img/calendar_32.png",
                                 }))
diff --git a/addons/im_livechat/views/im_livechat_channel_views.xml b/addons/im_livechat/views/im_livechat_channel_views.xml
index 86312084fbd..d08e427f2c4 100644
--- a/addons/im_livechat/views/im_livechat_channel_views.xml
+++ b/addons/im_livechat/views/im_livechat_channel_views.xml
@@ -60,8 +60,8 @@
                                         </p>
                                     </div>
                                     <div class="o_kanban_button">
-                                        <button t-if="record.are_you_inside.raw_value" name="action_quit" type="object" class="btn btn-sm btn-primary">Leave</button>
-                                        <button t-if="!record.are_you_inside.raw_value" name="action_join" type="object" class="btn btn-sm btn-primary">Join</button>
+                                        <button t-if="record.are_you_inside.raw_value" name="action_quit" type="object" class="btn btn-primary">Leave</button>
+                                        <button t-if="!record.are_you_inside.raw_value" name="action_join" type="object" class="btn btn-primary">Join</button>
                                     </div>
                                 </div>
                             </div>
diff --git a/addons/mail/static/src/xml/activity.xml b/addons/mail/static/src/xml/activity.xml
index ca07f810101..1ca80f46fcd 100644
--- a/addons/mail/static/src/xml/activity.xml
+++ b/addons/mail/static/src/xml/activity.xml
@@ -62,13 +62,13 @@
                             <t t-raw="activity.note"/>
                         </div>
                         <div class="o_thread_message_tools btn-group">
-                            <a role="button" href="#" class="btn btn-link btn-success text-muted btn-sm o_activity_done o_activity_link mr8" t-att-data-activity-id="activity.id" t-att-data-previous-activity-type-id="activity.activity_type_id[0]" data-toggle="popover">
+                            <a role="button" href="#" class="btn btn-link btn-success text-muted o_activity_done o_activity_link mr8" t-att-data-activity-id="activity.id" t-att-data-previous-activity-type-id="activity.activity_type_id[0]" data-toggle="popover">
                                 <i class="fa fa-check"/> Mark Done
                             </a>
-                            <a role="button" href="#" class="btn btn-link btn-default text-muted btn-sm o_activity_edit o_activity_link" t-att-data-activity-id="activity.id">
+                            <a role="button" href="#" class="btn btn-link btn-default text-muted o_activity_edit o_activity_link" t-att-data-activity-id="activity.id">
                                 <i class="fa fa-pencil"/> Edit
                             </a>
-                            <a role="button" href="#" class="btn btn-link btn-sm btn-danger text-muted o_activity_unlink o_activity_link" t-att-data-activity-id="activity.id">
+                            <a role="button" href="#" class="btn btn-link btn-danger text-muted o_activity_unlink o_activity_link" t-att-data-activity-id="activity.id">
                                 <i class="fa fa-times"/> Cancel
                             </a>
                         </div>
diff --git a/addons/mail/static/src/xml/chatter.xml b/addons/mail/static/src/xml/chatter.xml
index 9b6d0586bdc..63bf85adde4 100644
--- a/addons/mail/static/src/xml/chatter.xml
+++ b/addons/mail/static/src/xml/chatter.xml
@@ -44,7 +44,7 @@
 
         <!-- Add a button to open the full composer dialog -->
         <t t-jquery=".o_composer_button_add_attachment" t-operation="after">
-            <button tabindex="6" class="btn btn-sm btn-icon fa fa-expand o_composer_button_full_composer" type="button" title="Full composer" aria-label="Full composer"/>
+            <button tabindex="6" class="btn btn-icon fa fa-expand o_composer_button_full_composer" type="button" title="Full composer" aria-label="Full composer"/>
         </t>
     </t>
 
@@ -57,13 +57,13 @@
         @param {boolean} [scheduleActivityButton]
     -->
     <t t-name="mail.chatter.Buttons">
-        <button t-if="newMessageButton" type="button" class="btn btn-sm btn-link o_chatter_button_new_message" title="Send a message" disabled="disabled">
+        <button t-if="newMessageButton" type="button" class="btn btn-link o_chatter_button_new_message" title="Send a message" disabled="disabled">
             Send message
         </button>
-        <button t-if="logNoteButton" class="btn btn-sm btn-link o_chatter_button_log_note" title="Log a note. Followers will not be notified." disabled="disabled">
+        <button t-if="logNoteButton" class="btn btn-link o_chatter_button_log_note" title="Log a note. Followers will not be notified." disabled="disabled">
             Log note
         </button>
-        <button t-if="scheduleActivityButton" class="btn btn-sm btn-link o_chatter_button_schedule_activity" title="Log or schedule an activity" disabled="disabled">
+        <button t-if="scheduleActivityButton" class="btn btn-link o_chatter_button_schedule_activity" title="Log or schedule an activity" disabled="disabled">
             <i class="fa fa-clock-o" role="img" aria-label="Dates" title="Dates"/> <t t-if="isMobile">Activity</t><t t-else="">Schedule activity</t>
         </button>
     </t>
diff --git a/addons/mail/static/src/xml/composer.xml b/addons/mail/static/src/xml/composer.xml
index 849a37ae3d1..93061c3e4fd 100644
--- a/addons/mail/static/src/xml/composer.xml
+++ b/addons/mail/static/src/xml/composer.xml
@@ -11,16 +11,16 @@
                 <div class="o_composer_input">
                     <textarea class="o_input o_composer_text_field" tabindex="2" placeholder="Write something..."/>
                     <div class="o_chatter_composer_tools">
-                        <button tabindex="4" class="btn btn-sm btn-icon fa fa-smile-o o_composer_button_emoji" type="button" data-toggle="popover" title="Emojis" aria-label="Emojis"/>
-                        <button tabindex="5" class="btn btn-sm btn-icon fa fa-paperclip o_composer_button_add_attachment" type="button" aria-label="Add attachment" title="Add attachment"/>
-                        <button t-if="widget.options.isMobile" tabindex="3" class="btn btn-sm btn-icon fa fa-paper-plane-o o_composer_button_send" type="button" title="Send" aria-label="Send"/>
+                        <button tabindex="4" class="btn btn-icon fa fa-smile-o o_composer_button_emoji" type="button" data-toggle="popover" title="Emojis" aria-label="Emojis"/>
+                        <button tabindex="5" class="btn btn-icon fa fa-paperclip o_composer_button_add_attachment" type="button" aria-label="Add attachment" title="Add attachment"/>
+                        <button t-if="widget.options.isMobile" tabindex="3" class="btn btn-icon fa fa-paper-plane-o o_composer_button_send" type="button" title="Send" aria-label="Send"/>
                     </div>
                 </div>
              </div>
              <div class="o_composer_attachments_list"/>
          </div>
          <div class="o_composer_send">
-             <button tabindex="3" class="btn btn-sm btn-primary o_composer_button_send d-none d-md-inline-block" type="button"><t t-esc="widget.options.sendText"/></button>
+             <button tabindex="3" class="btn btn-primary o_composer_button_send d-none d-md-inline-block" type="button"><t t-esc="widget.options.sendText"/></button>
          </div>
          <span class="d-none">
             <t t-call="HiddenInputFile">
diff --git a/addons/mail/static/src/xml/discuss.xml b/addons/mail/static/src/xml/discuss.xml
index bb62bed5cca..f46c5a12300 100644
--- a/addons/mail/static/src/xml/discuss.xml
+++ b/addons/mail/static/src/xml/discuss.xml
@@ -181,16 +181,16 @@
     -->
     <t t-name="mail.discuss.ControlButtons">
         <div>
-            <button type="button" class="btn btn-primary btn-sm o_mail_discuss_button_invite d-none d-md-inline-block" title="Invite people">Invite</button>
-            <button type="button" class="btn btn-default btn-sm o_mail_discuss_button_mark_all_read d-none d-md-inline-block" title="Mark all as read">Mark all read</button>
-            <button type="button" class="btn btn-default btn-sm o_mail_discuss_button_unstar_all" title="Unstar all messages">Unstar all</button>
-            <button type="button" class="btn btn-default btn-sm o_mail_discuss_button_dm d-block d-md-none" title="New Message">New Message</button>
-            <button t-if="!disableAddThread" type="button" class="btn btn-default btn-sm o_mail_discuss_button_public o_mail_discuss_button_private d-block d-md-none" title="New Channel">New Channel</button>
-            <button type="button" class="btn btn-default btn-sm o_hidden o_mail_discuss_button_select_all" title="Select all messages to moderate">Select All</button>
-            <button type="button" class="btn btn-default btn-sm o_hidden o_mail_discuss_button_unselect_all" title="Unselect all messages to moderate">Unselect All</button>
-            <button type="button" data-decision="accept" class="btn btn-default btn-sm o_mail_discuss_button_moderate_all" title="Accept selected messages">Accept</button>
-            <button type="button" data-decision="reject" class="btn btn-default btn-sm o_mail_discuss_button_moderate_all" title="Reject selected messages">Reject</button>
-            <button type="button" data-decision="discard" class="btn btn-default btn-sm o_mail_discuss_button_moderate_all" title="Discard selected messages">Discard</button>
+            <button type="button" class="btn btn-primary o_mail_discuss_button_invite d-none d-md-inline-block" title="Invite people">Invite</button>
+            <button type="button" class="btn btn-default o_mail_discuss_button_mark_all_read d-none d-md-inline-block" title="Mark all as read">Mark all read</button>
+            <button type="button" class="btn btn-default o_mail_discuss_button_unstar_all" title="Unstar all messages">Unstar all</button>
+            <button type="button" class="btn btn-default o_mail_discuss_button_dm d-block d-md-none" title="New Message">New Message</button>
+            <button t-if="!disableAddThread" type="button" class="btn btn-default o_mail_discuss_button_public o_mail_discuss_button_private d-block d-md-none" title="New Channel">New Channel</button>
+            <button type="button" class="btn btn-default o_hidden o_mail_discuss_button_select_all" title="Select all messages to moderate">Select All</button>
+            <button type="button" class="btn btn-default o_hidden o_mail_discuss_button_unselect_all" title="Unselect all messages to moderate">Unselect All</button>
+            <button type="button" data-decision="accept" class="btn btn-default o_mail_discuss_button_moderate_all" title="Accept selected messages">Accept</button>
+            <button type="button" data-decision="reject" class="btn btn-default o_mail_discuss_button_moderate_all" title="Reject selected messages">Reject</button>
+            <button type="button" data-decision="discard" class="btn btn-default o_mail_discuss_button_moderate_all" title="Discard selected messages">Discard</button>
         </div>
     </t>
 
@@ -208,10 +208,10 @@
     <t t-name="mail.discuss_mobile">
         <div class="o_mail_discuss">
             <div class="o_mail_discuss_mobile_mailboxes_buttons">
-                <button type="button" class="btn btn-primary btn-sm d-inline d-md-none o_mailbox_inbox_item" title="Inbox" data-type="mailbox_inbox">
+                <button type="button" class="btn btn-primary d-inline d-md-none o_mailbox_inbox_item" title="Inbox" data-type="mailbox_inbox">
                     Inbox
                 </button>
-                <button type="button" class="btn btn-default btn-sm d-inline d-md-none o_mailbox_inbox_item" title="Starred" data-type="mailbox_starred">
+                <button type="button" class="btn btn-default d-inline d-md-none o_mailbox_inbox_item" title="Starred" data-type="mailbox_starred">
                     Starred
                 </button>
             </div>
diff --git a/addons/mail/static/src/xml/followers.xml b/addons/mail/static/src/xml/followers.xml
index add787b7e03..a19831308a6 100644
--- a/addons/mail/static/src/xml/followers.xml
+++ b/addons/mail/static/src/xml/followers.xml
@@ -7,7 +7,7 @@
     <t t-name="mail.Followers">
         <div class="o_followers">
             <div class="o_followers_title_box">
-                <button class="btn btn-sm btn-link dropdown-toggle" title="Dropdown menu - Followers"
+                <button class="btn btn-link dropdown-toggle" title="Dropdown menu - Followers"
                         data-toggle="dropdown" aria-expanded="false">
                     <i class="fa fa-user" role="img" aria-label="Dropdown menu - Followers"></i>
                     <span class="o_followers_count"/>
@@ -15,14 +15,14 @@
                 <ul class="dropdown-menu o_followers_list" role="menu"></ul>
             </div>
             <div class="o_followers_actions">
-                <div class="btn-group btn-group-sm o_subtypes_list">
-                    <button class="btn btn-sm btn-link o_followers_follow_button o_followers_notfollow">
+                <div class="btn-group o_subtypes_list">
+                    <button class="btn btn-link o_followers_follow_button o_followers_notfollow">
                         <span class="o_follow">Follow</span>
                         <span class="fa fa-times o_followers_unfollow"/>
                         <span class="o_followers_unfollow"> Unfollow</span>
                         <span class="fa fa-check o_followers_following"/>
                         <span class="o_followers_following"> Following</span>
-                    </button><button class="btn btn-sm btn-link dropdown-toggle" data-toggle="dropdown" aria-expanded="false">
+                    </button><button class="btn btn-link dropdown-toggle" data-toggle="dropdown" aria-expanded="false">
                         <span class="fa fa-bell" role="img" aria-label="Alarm menu" title="Alarm menu"/>
                     </button>
                     <ul class="dropdown-menu" role="menu"/>
diff --git a/addons/mail/static/src/xml/systray.xml b/addons/mail/static/src/xml/systray.xml
index 7f3d56d955d..2f506b926df 100644
--- a/addons/mail/static/src/xml/systray.xml
+++ b/addons/mail/static/src/xml/systray.xml
@@ -12,16 +12,16 @@
             <ul class="o_mail_systray_dropdown dropdown-menu" role="menu">
                 <li role="menuitem" t-if="widget.isMobile()">
                     <div class="o_mail_systray_mobile_header">
-                        <button type="button" class="btn btn-default btn-sm o_new_message"> New message </button>
+                        <button type="button" class="btn btn-default o_new_message"> New message </button>
                     </div>
                 </li>
                 <li role="menuitem" t-if="!widget.isMobile()" class="o_mail_systray_dropdown_top">
                     <div>
-                        <button type="button" class="btn btn-sm btn-link o_filter_button active"> All </button>
-                        <button type="button" class="btn btn-sm btn-link o_filter_button" data-filter='chat'> Chat </button>
-                        <button type="button" class="btn btn-sm btn-link o_filter_button" data-filter='channels'> Channels </button>
+                        <button type="button" class="btn btn-link o_filter_button active"> All </button>
+                        <button type="button" class="btn btn-link o_filter_button" data-filter='chat'> Chat </button>
+                        <button type="button" class="btn btn-link o_filter_button" data-filter='channels'> Channels </button>
                     </div>
-                    <button type="button" class="btn btn-sm btn-link o_new_message"> New message </button>
+                    <button type="button" class="btn btn-link o_new_message"> New message </button>
                 </li>
                 <li role="menuitem" class="o_mail_systray_dropdown_items"/>
                 <li role="menuitem" t-if="widget.isMobile()">
diff --git a/addons/mail/static/src/xml/thread.xml b/addons/mail/static/src/xml/thread.xml
index 2d877068694..41335c3f5f3 100644
--- a/addons/mail/static/src/xml/thread.xml
+++ b/addons/mail/static/src/xml/thread.xml
@@ -438,7 +438,7 @@
                 <span><i class="fa fa-spinner fa-spin" role="img" aria-label="Please wait" title="Please wait"/> Loading older messages... </span>
             </t>
             <t t-else="">
-                <button class="btn btn-sm btn-link">-------- Show older messages --------</button>
+                <button class="btn btn-link">-------- Show older messages --------</button>
             </t>
         </div>
     </t>
diff --git a/addons/mail/views/mail_channel_views.xml b/addons/mail/views/mail_channel_views.xml
index ceccbd6381a..df471961845 100644
--- a/addons/mail/views/mail_channel_views.xml
+++ b/addons/mail/views/mail_channel_views.xml
@@ -67,8 +67,8 @@
                                     <p class="oe_module_name">
                                         <field name="description"/>
                                     </p>
-                                    <button type="object" attrs="{'invisible':['|', ('is_subscribed','=',True), ('group_ids', '!=', [])]}" class="btn btn-primary pull-right btn-sm" name="channel_join_and_get_info">Join</button>
-                                    <button type="object" attrs="{'invisible':['|', ('is_subscribed','=',False), ('group_ids', '!=', [])]}" class="btn btn-default pull-right btn-sm" name="action_unfollow">Leave</button>
+                                    <button type="object" attrs="{'invisible':['|', ('is_subscribed','=',True), ('group_ids', '!=', [])]}" class="btn btn-primary pull-right" name="channel_join_and_get_info">Join</button>
+                                    <button type="object" attrs="{'invisible':['|', ('is_subscribed','=',False), ('group_ids', '!=', [])]}" class="btn btn-default pull-right" name="action_unfollow">Leave</button>
                                 </div>
                             </div>
                         </t>
@@ -89,7 +89,7 @@
                     <sheet>
                         <div class="oe_button_box" name="button_box">
                             <field name="is_moderator" invisible="1"/>
-                            <button class="btn btn-sm oe_stat_button" name="mail.mail_moderation_action" type="action" attrs="{'invisible':[('is_moderator', '=', False)]}" icon="fa-bars" context="{'search_default_channel_id': active_id}">
+                            <button class="btn oe_stat_button" name="mail.mail_moderation_action" type="action" attrs="{'invisible':[('is_moderator', '=', False)]}" icon="fa-bars" context="{'search_default_channel_id': active_id}">
                             <field string="Ban List" name="moderation_count" widget="statinfo"/>
                             </button>
                         </div>
@@ -155,7 +155,7 @@
                 </form>
             </field>
         </record>
-        
+
         <record id="mail_channel_view_tree" model="ir.ui.view">
             <field name="name">mail.channel.tree</field>
             <field name="model">mail.channel</field>
diff --git a/addons/mass_mailing/views/snippets_themes.xml b/addons/mass_mailing/views/snippets_themes.xml
index e262c86329f..b7a69de548c 100644
--- a/addons/mass_mailing/views/snippets_themes.xml
+++ b/addons/mass_mailing/views/snippets_themes.xml
@@ -650,8 +650,8 @@
                             </p>
                         </div>
                         <div class="small mt16">
-                            <a role="button" href="#" class="btn btn-sm btn-primary">Registration</a>
-                            <a role="button" href="#" class="btn btn-sm btn-link" style="margin-left:10px">More Info</a>
+                            <a role="button" href="#" class="btn btn-primary">Registration</a>
+                            <a role="button" href="#" class="btn btn-link" style="margin-left:10px">More Info</a>
                         </div>
                     </td>
                 </tr>
diff --git a/addons/mrp/static/src/xml/mrp.xml b/addons/mrp/static/src/xml/mrp.xml
index 75c2ce15422..e3c94ee0945 100644
--- a/addons/mrp/static/src/xml/mrp.xml
+++ b/addons/mrp/static/src/xml/mrp.xml
@@ -1,8 +1,8 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <templates>
     <t t-name="mrp.button">
-        <button type="button" class="btn btn-primary btn-sm o_mrp_bom_print">print</button>
-        <button type="button" class="btn btn-primary btn-sm ml8 o_mrp_bom_print_unfolded">print unfolded</button>
+        <button type="button" class="btn btn-primary o_mrp_bom_print">print</button>
+        <button type="button" class="btn btn-primary ml8 o_mrp_bom_print_unfolded">print unfolded</button>
     </t>
 
     <form class="form-inline" t-name="mrp.report_bom_search">
diff --git a/addons/payment/views/payment_views.xml b/addons/payment/views/payment_views.xml
index 5c19a13c4fc..b7fc6500ff0 100644
--- a/addons/payment/views/payment_views.xml
+++ b/addons/payment/views/payment_views.xml
@@ -153,9 +153,9 @@
                                     <t t-if="installed">
                                         <field name="environment" widget="label_selection" options="{'classes': {'test': 'warning', 'production': 'success'}}"/>
                                     </t>
-                                    <button t-if="!installed" type="object" class="btn btn-default pull-right btn-sm" name="button_immediate_install">Install</button>
-                                    <button t-if="installed and !record.website_published.raw_value" type="edit" class="btn btn-primary pull-right btn-sm">Activate</button>
-                                    <button t-if="installed and record.website_published.raw_value" type="edit" class="btn btn-primary pull-right btn-sm">Configure</button>
+                                    <button t-if="!installed" type="object" class="btn btn-default pull-right" name="button_immediate_install">Install</button>
+                                    <button t-if="installed and !record.website_published.raw_value" type="edit" class="btn btn-primary pull-right">Activate</button>
+                                    <button t-if="installed and record.website_published.raw_value" type="edit" class="btn btn-primary pull-right">Configure</button>
                                 </div>
                             </div>
                         </t>
diff --git a/addons/sale_timesheet/static/src/xml/timesheet_plan.xml b/addons/sale_timesheet/static/src/xml/timesheet_plan.xml
index b11d055c9e0..b127f433735 100644
--- a/addons/sale_timesheet/static/src/xml/timesheet_plan.xml
+++ b/addons/sale_timesheet/static/src/xml/timesheet_plan.xml
@@ -4,7 +4,7 @@
     <t t-name="project.plan.ControlButtons">
         <div>
         	<t t-foreach="buttons" t-as="button">
-            	<button type="button" class="btn btn-primary btn-sm o_timesheet_plan_btn_action" t-att-title="button['label']" t-att-data-context="button['context']" t-att-data-action-id="button['action_id']">
+            	<button type="button" class="btn btn-primary o_timesheet_plan_btn_action" t-att-title="button['label']" t-att-data-context="button['context']" t-att-data-action-id="button['action_id']">
             		<t t-esc="button['label']"/>
             	</button>
 
diff --git a/addons/sale_timesheet/views/hr_timesheet_templates.xml b/addons/sale_timesheet/views/hr_timesheet_templates.xml
index 875d797fcb9..31b334132d4 100644
--- a/addons/sale_timesheet/views/hr_timesheet_templates.xml
+++ b/addons/sale_timesheet/views/hr_timesheet_templates.xml
@@ -25,7 +25,7 @@
 
                             <div class="o_timesheet_plan_stat_buttons oe_button_box">
                                 <t t-foreach="stat_buttons" t-as="stat_button">
-                                    <button class="btn btn-sm oe_stat_button" t-att-data-domain="stat_button['domain']" t-att-data-res-model="stat_button['res_model']">
+                                    <button class="btn oe_stat_button" t-att-data-domain="stat_button['domain']" t-att-data-res-model="stat_button['res_model']">
                                         <div t-attf-class="fa fa-fw o_button_icon #{stat_button['icon']}" role="img" aria-label="Statistics" title="Statistics"></div>
                                         <div name="task_count" class="o_field_widget o_stat_info o_readonly_modifier" t-att-title="stat_button['name']">
                                             <span class="o_stat_value" t-if="stat_button.get('count')">
diff --git a/addons/stock/static/src/xml/stock_traceability_report_backend.xml b/addons/stock/static/src/xml/stock_traceability_report_backend.xml
index d6a30fb9414..1c60cd85b23 100644
--- a/addons/stock/static/src/xml/stock_traceability_report_backend.xml
+++ b/addons/stock/static/src/xml/stock_traceability_report_backend.xml
@@ -3,7 +3,7 @@
 <templates>
 
     <t t-name="stockReports.buttons">
-        <button type="button" class='btn btn-primary btn-sm o_stock-widget-pdf'>PRINT</button>
+        <button type="button" class='btn btn-primary o_stock-widget-pdf'>PRINT</button>
     </t>
 
     <div role="dialog" t-name='stockReports.errorModal' class="modal" id="editable_error" tabindex="-1" data-backdrop="static" style="z-index:9999;">
diff --git a/addons/web/static/src/js/core/dom.js b/addons/web/static/src/js/core/dom.js
index e82db818bb5..81f5bfec5c0 100644
--- a/addons/web/static/src/js/core/dom.js
+++ b/addons/web/static/src/js/core/dom.js
@@ -211,8 +211,7 @@ return {
      * @param {string} [options.attrs.class='btn-default']
      *        Note: automatically completed with "btn btn-X"
      *        (@see options.size for the value of X)
-     * @param {string} [options.size='sm'] - @see options.attrs.class
-     *        Note: use 'md' for no sizing class
+     * @param {string} [options.size] - @see options.attrs.class
      * @param {string} [options.icon]
      *        The specific fa icon class (for example "fa-home") or an URL for
      *        an image to use as icon.
@@ -235,8 +234,8 @@ return {
         }
 
         jQueryParams.class = 'btn';
-        if (options.size !== 'md') {
-            jQueryParams.class += (' btn-' + (options.size || 'sm'));
+        if (options.size) {
+            jQueryParams.class += (' btn-' + options.size);
         }
         jQueryParams.class += (' ' + (extraClasses || 'btn-default'));
 
diff --git a/addons/web/static/src/js/views/search/groupby_menu.js b/addons/web/static/src/js/views/search/groupby_menu.js
index 7b3b8e31fef..7be61ae6606 100644
--- a/addons/web/static/src/js/views/search/groupby_menu.js
+++ b/addons/web/static/src/js/views/search/groupby_menu.js
@@ -78,7 +78,7 @@ var GroupByMenu = DropdownMenu.extend({
         if (options && options.headerStyle === 'primary') {
             style = {
                 el: {class: 'btn-group o_graph_groupbys_menu o_dropdown', attrs: {'role': 'group'}},
-                mainButton: {class: 'btn btn-primary btn-sm dropdown-toggle'},
+                mainButton: {class: 'btn btn-primary dropdown-toggle'},
             };
         }
         var dropdownHeader = {
diff --git a/addons/web/static/src/js/widgets/dropdown_menu.js b/addons/web/static/src/js/widgets/dropdown_menu.js
index a3a83519678..77dd7be10d0 100644
--- a/addons/web/static/src/js/widgets/dropdown_menu.js
+++ b/addons/web/static/src/js/widgets/dropdown_menu.js
@@ -49,7 +49,7 @@ var DropdownMenu = Widget.extend({
         // the style used is the one used in the search view
         this.dropdownStyle = dropdownHeader.style || {
                 el: {class: 'btn-group o_dropdown', attrs: {}},
-                mainButton: {class: 'o_dropdown_toggler_btn btn btn-sm btn-default dropdown-toggle'},
+                mainButton: {class: 'o_dropdown_toggler_btn btn btn-default dropdown-toggle'},
             };
         this.items = items;
         _.each(this.items, this._prepareItem.bind(this));
diff --git a/addons/web/static/src/xml/base.xml b/addons/web/static/src/xml/base.xml
index 14b49945fcb..5e64eb6d0a9 100644
--- a/addons/web/static/src/xml/base.xml
+++ b/addons/web/static/src/xml/base.xml
@@ -123,7 +123,7 @@
         </div>
         <div class="o_notification_content" t-if="widget.message"><t t-raw="widget.message"/></div>
         <div t-if="widget.buttons.length" class="o_buttons">
-            <button t-foreach="widget.buttons" t-as="button" t-attf-class="btn btn-sm #{button.primary ? 'btn-primary' : 'btn-default'}" type="button">
+            <button t-foreach="widget.buttons" t-as="button" t-attf-class="btn #{button.primary ? 'btn-primary' : 'btn-default'}" type="button">
                 <t t-if="button.icon">
                     <i t-if="button.icon.indexOf('fa-') === 0" t-attf-class="fa fa-fw o_button_icon #{button.icon}" role="img" t-att-aria-label="button.name" t-att-title="button.name"/>
                     <img t-else="" t-att-src="button.icon" t-att-alt="button.name"/>
@@ -143,7 +143,7 @@
 </div>
 <div t-name="CrashManager.error" class="o_dialog_error">
     <div class="alert alert-warning clearfix" role="alert">
-        <button class="btn btn-sm btn-primary pull-right ml8 o_clipboard_button">
+        <button class="btn btn-primary pull-right ml8 o_clipboard_button">
             <i class="fa fa-clipboard mr8"/>Copy the full error to clipboard
         </button>
         <p><b>An error occurred</b></p>
@@ -151,7 +151,7 @@
     </div>
 
     <t t-set="errUID" t-value="_.uniqueId()"/>
-    <button class="btn btn-sm btn-link" t-att-data-target="'#o_error_detail' + errUID" data-toggle="collapse">See details</button>
+    <button class="btn btn-link" t-att-data-target="'#o_error_detail' + errUID" data-toggle="collapse">See details</button>
     <div t-att-id="'o_error_detail' + errUID" class="collapse alert alert-danger o_error_detail" role="alert">
         <pre><t t-esc="error.message"/></pre>
         <pre><t t-esc="error.data.debug"/></pre>
@@ -175,8 +175,8 @@
             </tr>
         </table>
 
-        <button type="button" class="btn btn-sm btn-primary oe_form_button">Change Password</button>
-        <button type="button" class="btn btn-sm btn-default oe_form_button oe_form_button_cancel" href="javascript:void(0)">Cancel</button>
+        <button type="button" class="btn btn-primary oe_form_button">Change Password</button>
+        <button type="button" class="btn btn-default oe_form_button oe_form_button_cancel" href="javascript:void(0)">Cancel</button>
     </div>
 </form>
 
@@ -191,7 +191,7 @@
         <div class="o_cp_right">
             <div class="btn-group o_search_options" role="search"/>
             <nav class="o_cp_pager" role="search" aria-label="Pager"/>
-            <nav class="btn-group btn-group-sm o_cp_switch_buttons" role="toolbar" aria-label="View switcher"/>
+            <nav class="btn-group o_cp_switch_buttons" role="toolbar" aria-label="View switcher"/>
         </div>
     </div>
 </t>
@@ -342,7 +342,7 @@
 <t t-name="Sidebar">
     <t t-foreach="widget.sections" t-as="section">
         <div class="btn-group o_dropdown">
-            <button t-if="section.name != 'buttons'" class="o_dropdown_toggler_btn btn btn-sm btn-default dropdown-toggle" data-toggle="dropdown" aria-expanded="false">
+            <button t-if="section.name != 'buttons'" class="o_dropdown_toggler_btn btn btn-default dropdown-toggle" data-toggle="dropdown" aria-expanded="false">
                 <t t-if="section.name == 'files'" t-raw="widget.items[section.name].length || ''"/>
                 <t t-esc="section.label"/> <span class="caret"/>
             </button>
@@ -393,14 +393,14 @@
 <t t-name="ListView.buttons">
     <div class="o_list_buttons" role="toolbar" aria-label="Main actions">
         <t t-if="widget.is_action_enabled('create')">
-            <button type="button" class="btn btn-primary btn-sm o_list_button_add" accesskey="c">
+            <button type="button" class="btn btn-primary o_list_button_add" accesskey="c">
                 Create
             </button>
         </t>
-        <button type="button" class="btn btn-primary btn-sm o_list_button_save" accesskey="s">
+        <button type="button" class="btn btn-primary o_list_button_save" accesskey="s">
             Save
         </button>
-        <button type="button" class="btn btn-default btn-sm o_list_button_discard" accesskey="j">
+        <button type="button" class="btn btn-default o_list_button_discard" accesskey="j">
             Discard
         </button>
     </div>
@@ -409,21 +409,21 @@
 <t t-name="FormView.buttons">
     <div class="o_form_buttons_view" role="toolbar" aria-label="Main actions">
         <button t-if="widget.is_action_enabled('edit')" type="button"
-                class="btn btn-primary btn-sm o_form_button_edit" accesskey="a">
+                class="btn btn-primary o_form_button_edit" accesskey="a">
             Edit
         </button>
         <button t-if="widget.is_action_enabled('create')" type="button"
-                class="btn btn-default btn-sm o_form_button_create" accesskey="c">
+                class="btn btn-default o_form_button_create" accesskey="c">
             Create
         </button>
     </div>
     <div class="o_form_buttons_edit" role="toolbar" aria-label="Main actions">
         <button type="button"
-                class="btn btn-primary btn-sm o_form_button_save" accesskey="s">
+                class="btn btn-primary o_form_button_save" accesskey="s">
             Save
         </button>
         <button type="button"
-                class="btn btn-default btn-sm o_form_button_cancel" accesskey="j">
+                class="btn btn-default o_form_button_cancel" accesskey="j">
             Discard
         </button>
     </div>
@@ -447,7 +447,7 @@
 <t t-name="FormButton.tooltip">
     <div class="oe_tooltip_string" role="tooltip">
         <div class="tooltip-inner">
-            Hit ENTER to 
+            Hit ENTER to
             <t t-esc="title"></t>
         </div>
     </div>
@@ -509,8 +509,8 @@
     </table>
 </form>
 <t t-name="GraphView.buttons">
-    <div class="btn-group btn-group-sm" role="toolbar" aria-label="Main actions">
-        <button class="btn btn-primary btn-sm dropdown-toggle" data-toggle="dropdown" aria-expanded="false">
+    <div class="btn-group" role="toolbar" aria-label="Main actions">
+        <button class="btn btn-primary dropdown-toggle" data-toggle="dropdown" aria-expanded="false">
             Measures <span class="caret"/>
         </button>
         <ul class="dropdown-menu o_graph_measures_list" role="menu">
@@ -521,7 +521,7 @@
             <li data-field="__count__"><a role="menuitem" href="#">Count</a></li>
         </ul>
     </div>
-    <div class="btn-group btn-group-sm" role="toolbar" aria-label="Change graph">
+    <div class="btn-group" role="toolbar" aria-label="Change graph">
         <button class="btn btn-default fa fa-bar-chart-o o_graph_button" title="Bar Chart" aria-label="Bar Chart" data-mode="bar"/>
         <button class="btn btn-default fa fa-line-chart o_graph_button" title="Line Chart" aria-label="Line Chart" data-mode="line"/>
         <button class="btn btn-default fa fa-pie-chart o_graph_button" title="Pie Chart" aria-label="Pie Chart" data-mode="pie"/>
@@ -538,8 +538,8 @@
     <div class="o_field_selection"/>
 </div>
 <t t-name="PivotView.buttons">
-    <div class="btn-group btn-group-sm" role="toolbar" aria-label="Main actions">
-        <button class="btn btn-primary btn-sm dropdown-toggle" data-toggle="dropdown" aria-expanded="false">
+    <div class="btn-group" role="toolbar" aria-label="Main actions">
+        <button class="btn btn-primary dropdown-toggle" data-toggle="dropdown" aria-expanded="false">
             Measures <span class="caret"/>
         </button>
         <ul class="dropdown-menu o_pivot_measures_list" role="menu">
@@ -550,7 +550,7 @@
             <li data-field="__count"><a role="menuitem" href="#">Count</a></li>
         </ul>
     </div>
-    <div class="btn-group btn-group-sm" role="toolbar" aria-label="Pivot settings">
+    <div class="btn-group" role="toolbar" aria-label="Pivot settings">
         <button class="btn btn-default fa fa-expand o_pivot_flip_button" title="Flip axis" aria-label="Flip axis"/>
         <button class="btn btn-default fa fa-arrows-alt o_pivot_expand_button" title="Expand all" aria-label="Expand all"/>
         <button class="btn btn-default fa fa-download o_pivot_download" title="Download xls" aria-label="Download xls"/>
@@ -901,7 +901,7 @@
 </t>
 <t t-name="FieldStatus.content">
     <t t-if="selection_folded.length">
-        <button type="button" class="btn btn-sm o_arrow_button btn-default dropdown-toggle" data-toggle="dropdown" aria-expanded="false">More <span class="caret"/></button>
+        <button type="button" class="btn o_arrow_button btn-default dropdown-toggle" data-toggle="dropdown" aria-expanded="false">More <span class="caret"/></button>
         <ul class="dropdown-menu o-status-more" role="menu">
             <li t-foreach="selection_folded" t-as="i">
                 <t t-call="FieldStatus.content.button"/>
@@ -915,15 +915,15 @@
 <t t-name="FieldStatus.content.button">
     <t t-set="disabled" t-value="!clickable"/>
     <button type="button" t-att-data-value="i.id" disabled="disabled" title="Current state" aria-pressed="true"
-        class="btn btn-sm o_arrow_button btn-primary disabled" t-if="i.selected" aria-current="step">
+        class="btn o_arrow_button btn-primary disabled" t-if="i.selected" aria-current="step">
         <t t-esc="i.display_name" role="img" t-attf-aria-label="#{i.display_name} is current state"/>
     </button>
     <button type="button" t-att-data-value="i.id" disabled="disabled" title="Not active state" aria-pressed="false"
-        class="btn btn-sm o_arrow_button btn-default disabled" t-if="!i.selected and disabled">
+        class="btn o_arrow_button btn-default disabled" t-if="!i.selected and disabled">
         <t t-esc="i.display_name" role="img" t-attf-aria-label="#{i.display_name} is not current state"/>
     </button>
     <button type="button" t-att-data-value="i.id" title="Not active state, click to change it" aria-pressed="false"
-        class="btn btn-sm o_arrow_button btn-default" t-if="!i.selected and !disabled">
+        class="btn o_arrow_button btn-default" t-if="!i.selected and !disabled">
         <t t-esc="i.display_name" role="img" t-attf-aria-label="Click to change current state to #{i.display_name}"/>
     </button>
 </t>
@@ -970,9 +970,9 @@
             t-att-tabindex="widget.attrs.tabindex"
             t-att-autofocus="widget.attrs.autofocus"/>
 
-        <button type="button" class="btn btn-sm btn-primary o_select_file_button" title="Select">Upload your file</button>
-        <button type="button" class="btn btn-sm btn-default fa fa-pencil o_select_file_button" title="Select" aria-label="Select"/>
-        <button type="button" class="btn btn-sm btn-default fa fa-trash-o o_clear_file_button" title="Clear" aria-label="Clear"/>
+        <button type="button" class="btn btn-primary o_select_file_button" title="Select">Upload your file</button>
+        <button type="button" class="btn btn-default fa fa-pencil o_select_file_button" title="Select" aria-label="Select"/>
+        <button type="button" class="btn btn-default fa fa-trash-o o_clear_file_button" title="Clear" aria-label="Clear"/>
 
         <span class="o_form_binary_progress">Uploading...</span>
         <t t-call="HiddenInputFile">
@@ -1001,9 +1001,9 @@
     <div class="o_field_pdfviewer" aria-atomic="true">
         <div t-if="widget.mode !== 'readonly'" class="o_form_pdf_controls mt8" role="toolbar" aria-label="PDF controls">
             <span class="o_form_binary_progress">Uploading...</span>
-            <button type="button" class="btn btn-sm btn-primary o_select_file_button" title="Select">Upload your file</button>
-            <button class="btn btn-sm btn-default fa fa-pencil o_select_file_button" title="Select" aria-label="Select" type="button"></button>
-            <button class="btn btn-sm btn-default fa fa-trash-o o_clear_file_button" title="Clear" aria-label="Clear" type="button"></button>
+            <button type="button" class="btn btn-primary o_select_file_button" title="Select">Upload your file</button>
+            <button class="btn btn-default fa fa-pencil o_select_file_button" title="Select" aria-label="Select" type="button"></button>
+            <button class="btn btn-default fa fa-trash-o o_clear_file_button" title="Clear" aria-label="Clear" type="button"></button>
         </div>
         <iframe class="o_pdfview_iframe o_field_pdfviewer"/>
         <t t-call="HiddenInputPDFFile">
@@ -1118,7 +1118,7 @@
         </select>
     </li>
     <li t-if="widget.generatorMenuIsOpen" class="o_generator_menu">
-        <button type="button" class="btn btn-primary btn-sm o_apply_group o_add_group" tabindex="-1">Apply</button>
+        <button type="button" class="btn btn-primary o_apply_group o_add_group" tabindex="-1">Apply</button>
     </li>
 </t>
 
@@ -1128,8 +1128,8 @@
         <a href="#">Add Custom Filter</a>
     </li>
     <li class="o_add_filter_menu">
-        <button class="btn btn-primary btn-sm o_apply_filter" type="button">Apply</button>
-        <button class="btn btn-default btn-sm o_add_condition" type="button">
+        <button class="btn btn-primary o_apply_filter" type="button">Apply</button>
+        <button class="btn btn-default o_add_condition" type="button">
             <span class="fa fa-plus-circle"/>
             Add a condition
         </button>
@@ -1144,7 +1144,7 @@
 </div>
 <t t-name="SearchViewMobile">
     <div class="o_searchview" role="search" aria-autocomplete="list">
-        <button class="o_enable_searchview btn btn-sm fa fa-search"/>
+        <button class="o_enable_searchview btn fa fa-search"/>
         <div class="o_mobile_search o_hidden">
             <div class="o_mobile_search_header">
                 <span class="o_mobile_search_close pull-left mt16 mb16 mr8 ml16">
@@ -1276,7 +1276,7 @@
 </t>
 
 <div t-name="SearchView.FavoriteMenu" class="btn-group o_dropdown">
-    <button class="o_dropdown_toggler_btn btn btn-sm btn-default dropdown-toggle" data-toggle="dropdown" aria-expanded="false" tabindex="-1" aria-label="Favorites" title="Favorites">
+    <button class="o_dropdown_toggler_btn btn btn-default dropdown-toggle" data-toggle="dropdown" aria-expanded="false" tabindex="-1" aria-label="Favorites" title="Favorites">
         <span class="fa fa-star"/> Favorites <span t-attf-class="#{widget.isMobile ? 'fa fa-chevron-right pull-right mt4' : 'caret'}"/>
     </button>
     <ul class="dropdown-menu o_favorites_menu" role="menu">
@@ -1295,7 +1295,7 @@
             <span><div class="o_checkbox"><input type="checkbox"/><span/></div> Share with all users </span><span class="fa fa-users" role="img" aria-label="Users" title="Users"/>
         </li>
         <li class="o_save_name">
-            <button role="menuitem" type="button" class="btn btn-primary btn-sm">Save</button>
+            <button role="menuitem" type="button" class="btn btn-primary">Save</button>
         </li>
     </ul>
 </div>
@@ -1331,11 +1331,11 @@
             <div class="o_left_field_panel"/>
         </div>
         <div class="o_center_panel">
-            <button type="button" class="btn btn-sm btn-default o_add_field">Add</button>
-            <button type="button" class="btn btn-sm btn-default o_remove_field">Remove</button>
-            <button type="button" class="btn btn-sm btn-default o_remove_all_field">Remove All</button>
-            <button type="button" class="btn btn-sm btn-default o_move_up">Move Up</button>
-            <button type="button" class="btn btn-sm btn-default o_move_down">Move Down</button>
+            <button type="button" class="btn btn-default o_add_field">Add</button>
+            <button type="button" class="btn btn-default o_remove_field">Remove</button>
+            <button type="button" class="btn btn-default o_remove_all_field">Remove All</button>
+            <button type="button" class="btn btn-default o_move_up">Move Up</button>
+            <button type="button" class="btn btn-default o_move_down">Move Down</button>
         </div>
         <div class="o_right_panel">
             <h4>
@@ -1363,7 +1363,7 @@
     </t>
 </t>
 <t t-name="Export.SaveList">
-    <label>Save as:</label> <input type="text"/><button type="button" class="btn btn-sm btn-default">Ok</button>
+    <label>Save as:</label> <input type="text"/><button type="button" class="btn btn-default">Ok</button>
 </t>
 <t t-name="Export.SavedList">
     <label>Saved exports: </label>
@@ -1373,7 +1373,7 @@
             <option t-att-value="export.id"><t t-esc="export.name"/></option>
         </t>
     </select>
-    <button type="button" class="btn btn-sm btn-default o_delete_exported_list">Delete</button>
+    <button type="button" class="btn btn-default o_delete_exported_list">Delete</button>
 </t>
 
 <t t-name="Throbber">
@@ -1420,7 +1420,7 @@
     <span class="o_pager_counter">
         <span class="o_pager_value"></span> / <span class="o_pager_limit"></span>
     </span>
-    <span class="btn-group btn-group-sm" aria-atomic="true">
+    <span class="btn-group" aria-atomic="true">
         <!-- accesskeys not wanted in X2Many widgets -->
         <t t-if="widget.options.withAccessKey">
             <t t-set="att_prev" t-value="{'accesskey': 'p'}" />
@@ -1519,7 +1519,7 @@
 </t>
 
 <t t-name="AttachDocument">
-    <button class="btn btn-sm btn-default o_attachment_button">
+    <button class="btn btn-default o_attachment_button">
         <span class="o_attach_document"><t t-esc="widget.node.attrs.string"/></span>
         <span class="d-none">
             <t t-call="HiddenInputFile">
diff --git a/addons/web/static/src/xml/kanban.xml b/addons/web/static/src/xml/kanban.xml
index 4b62f52cda8..7fd461a7c94 100644
--- a/addons/web/static/src/xml/kanban.xml
+++ b/addons/web/static/src/xml/kanban.xml
@@ -2,7 +2,7 @@
 
 <t t-name="KanbanView.buttons">
     <div>
-        <button type="button" t-attf-class="btn #{btnClass} btn-sm o-kanban-button-new" accesskey="c">
+        <button type="button" t-attf-class="btn #{btnClass} o-kanban-button-new" accesskey="c">
             <t t-esc="create_text || _t('Create')"/>
         </button>
     </div>
@@ -53,7 +53,7 @@
                 <div class="input-group">
                     <input type="text" class="o_input" placeholder="Column title"/>
                     <span class="input-group-btn">
-                        <button class="btn btn-sm btn-primary o_kanban_add" type="button">Add</button>
+                        <button class="btn btn-primary o_kanban_add" type="button">Add</button>
                     </span>
                 </div>
                 <t t-if="widget.examples">
@@ -70,9 +70,9 @@
 
 <t t-name="KanbanView.RecordQuickCreate.buttons">
     <div>
-        <button class="btn btn-sm btn-primary o_kanban_add">Add</button>
-        <button class="btn btn-sm btn-primary o_kanban_edit">Edit</button>
-        <button class="btn btn-sm btn-default o_kanban_cancel ml8">Discard</button>
+        <button class="btn btn-primary o_kanban_add">Add</button>
+        <button class="btn btn-primary o_kanban_edit">Edit</button>
+        <button class="btn btn-default o_kanban_cancel ml8">Discard</button>
     </div>
 </t>
 
diff --git a/addons/web/static/src/xml/report.xml b/addons/web/static/src/xml/report.xml
index c578add8ce9..927502e19ac 100644
--- a/addons/web/static/src/xml/report.xml
+++ b/addons/web/static/src/xml/report.xml
@@ -8,14 +8,14 @@
     <!-- Buttons of the Control Panel -->
     <t t-name="report.client_action.ControlButtons">
         <div class="o_report_no_edit_mode">
-            <button type="button" class="btn btn-primary btn-sm o_report_print" title="Print">Print</button>
+            <button type="button" class="btn btn-primary o_report_print" title="Print">Print</button>
         </div>
         <div class="o_edit_mode_available">
-            <button type="button" class="btn btn-default btn-sm o_report_edit" title="Edit">Edit</button>
+            <button type="button" class="btn btn-default o_report_edit" title="Edit">Edit</button>
         </div>
         <div class="o_report_edit_mode">
-            <button type="button" class="btn btn-primary btn-sm o_report_save" title="Save">Save</button>
-            <button type="button" class="btn btn-default btn-sm o_report_discard" title="Discard">Discard</button>
+            <button type="button" class="btn btn-primary o_report_save" title="Save">Save</button>
+            <button type="button" class="btn btn-default o_report_discard" title="Discard">Discard</button>
         </div>
     </t>
 </template>
\ No newline at end of file
diff --git a/addons/web/static/src/xml/web_calendar.xml b/addons/web/static/src/xml/web_calendar.xml
index b3c0e614d90..daf378ff3c6 100644
--- a/addons/web/static/src/xml/web_calendar.xml
+++ b/addons/web/static/src/xml/web_calendar.xml
@@ -64,14 +64,14 @@
     <t t-name="CalendarView.buttons">
         <div class="o_calendar_buttons">
             <t t-if="!isMobile">
-                <button class="o_calendar_button_prev btn btn-sm btn-primary" aria-label="Previous" title="Previous"><span class="fa fa-arrow-left"/></button>
-                <button class="o_calendar_button_today btn btn-sm btn-primary">Today</button>
-                <button class="o_calendar_button_next btn btn-sm btn-primary" aria-label="Next" title="Next"><span class="fa fa-arrow-right"/></button>
+                <button class="o_calendar_button_prev btn btn-primary" aria-label="Previous" title="Previous"><span class="fa fa-arrow-left"/></button>
+                <button class="o_calendar_button_today btn btn-primary">Today</button>
+                <button class="o_calendar_button_next btn btn-primary" aria-label="Next" title="Next"><span class="fa fa-arrow-right"/></button>
             </t>
-            <div class="btn-group btn-group-sm">
-                <button type="button" class="o_calendar_button_day btn btn-sm btn-default">Day</button>
-                <button type="button" class="o_calendar_button_week btn btn-sm btn-default">Week</button>
-                <button type="button" class="o_calendar_button_month btn btn-sm btn-default">Month</button>
+            <div class="btn-group">
+                <button type="button" class="o_calendar_button_day btn btn-default">Day</button>
+                <button type="button" class="o_calendar_button_week btn btn-default">Week</button>
+                <button type="button" class="o_calendar_button_month btn btn-default">Month</button>
             </div>
         </div>
     </t>
diff --git a/addons/web/static/tests/fields/relational_fields_tests.js b/addons/web/static/tests/fields/relational_fields_tests.js
index 2001bed1d65..fd81fba68ab 100644
--- a/addons/web/static/tests/fields/relational_fields_tests.js
+++ b/addons/web/static/tests/fields/relational_fields_tests.js
@@ -2622,7 +2622,7 @@ QUnit.module('relational_fields', {
         });
 
         // First round: add 51 records in batch
-        form.$buttons.find('.btn.btn-primary.btn-sm.o_form_button_edit').click();
+        form.$buttons.find('.btn.btn-primary.o_form_button_edit').click();
         form.$('.o_field_x2many_list_row_add a').click();
 
         var $modal = $('.modal-lg');
@@ -2632,16 +2632,16 @@ QUnit.module('relational_fields', {
 
         $modal.find('thead input[type=checkbox]').click(); //select all the records we created in batch + 'gold'
 
-        $modal.find('.btn.btn-sm.btn-primary.o_select_button').click();
+        $modal.find('.btn.btn-primary.o_select_button').click();
 
         var m2m_records = form.$('.o_field_many2many.o_field_widget.o_field_x2many.o_field_x2many_list .o_data_cell:not(.o_many2many_tags_cell)');
         assert.equal(m2m_records.length, 51,
             'We should have added all the records present in the search view to the m2m field'); // the 50 in batch + 'gold'
 
-        form.$buttons.find('.btn.btn-primary.btn-sm.o_form_button_save').click();
+        form.$buttons.find('.btn.btn-primary.o_form_button_save').click();
 
         // Secound round: remove one record
-        form.$buttons.find('.btn.btn-primary.btn-sm.o_form_button_edit').click();
+        form.$buttons.find('.btn.btn-primary.o_form_button_edit').click();
         var trash_buttons = form.$('.o_field_many2many.o_field_widget.o_field_x2many.o_field_x2many_list .o_list_record_remove');
 
         trash_buttons.first().click();
@@ -2660,7 +2660,7 @@ QUnit.module('relational_fields', {
 
         $modal.find('thead input[type=checkbox]').click();
 
-        $modal.find('.btn.btn-sm.btn-primary.o_select_button').click();
+        $modal.find('.btn.btn-primary.o_select_button').click();
 
         pager_limit = form.$('.o_field_many2many.o_field_widget.o_field_x2many.o_field_x2many_list .o_pager_limit');
         assert.equal(pager_limit.text(), '51',
diff --git a/addons/web/static/tests/services/notification_service_tests.js b/addons/web/static/tests/services/notification_service_tests.js
index feb3a600550..e2619e393f4 100644
--- a/addons/web/static/tests/services/notification_service_tests.js
+++ b/addons/web/static/tests/services/notification_service_tests.js
@@ -184,7 +184,7 @@ QUnit.module('Services', {
         var $notification = $('body .o_notification_manager .o_notification');
         assert.strictEqual($notification.eq(0).find('.o_close').length, 1, "should display the close button in notification");
         assert.strictEqual(_.str.trim($notification.eq(0).html().replace(/\s+/g, ' ')),
-            "<a aria-label=\"Close\" class=\"fa fa-times o_close\" href=\"#\" title=\"Close\"></a> <div class=\"o_notification_title\"> <span role=\"img\" aria-label=\"Notification undefined\" class=\"o_icon fa fa-3x fa-question-circle-o\" title=\"Notification undefined\"></span> a0 </div> <div class=\"o_notification_content\">b0</div> <div class=\"o_buttons\"> <button type=\"button\" class=\"btn btn-sm btn-primary\"> <span>accept0</span> </button><button type=\"button\" class=\"btn btn-sm btn-default\"> <span>refuse0</span> </button> </div>",
+            "<a aria-label=\"Close\" class=\"fa fa-times o_close\" href=\"#\" title=\"Close\"></a> <div class=\"o_notification_title\"> <span role=\"img\" aria-label=\"Notification undefined\" class=\"o_icon fa fa-3x fa-question-circle-o\" title=\"Notification undefined\"></span> a0 </div> <div class=\"o_notification_content\">b0</div> <div class=\"o_buttons\"> <button type=\"button\" class=\"btn btn-primary\"> <span>accept0</span> </button><button type=\"button\" class=\"btn btn-default\"> <span>refuse0</span> </button> </div>",
             "should display notification");
 
         $notification.find('.o_buttons button:contains(accept0)').click();
diff --git a/addons/web/static/tests/views/form_tests.js b/addons/web/static/tests/views/form_tests.js
index a7463d1ef11..868101833aa 100644
--- a/addons/web/static/tests/views/form_tests.js
+++ b/addons/web/static/tests/views/form_tests.js
@@ -1077,7 +1077,7 @@ QUnit.module('Views', {
                 return this._super.apply(this, arguments);
             },
         });
-        assert.strictEqual(form.$('button.btn.btn-sm i.fa.fa-check').length, 1,
+        assert.strictEqual(form.$('button.btn i.fa.fa-check').length, 1,
                         "should contain a button with correct content");
 
         assert.strictEqual(form.$('.o_form_statusbar button').length, 2,
@@ -1142,37 +1142,37 @@ QUnit.module('Views', {
             res_id: 2,
         });
 
-        assert.strictEqual(form.$('button[name="0"]').attr('class'), 'btn btn-sm btn-default',
+        assert.strictEqual(form.$('button[name="0"]').attr('class'), 'btn btn-default',
             "header buttons without any class should receive the correct classes");
-        assert.strictEqual(form.$('button[name="1"]').attr('class'), 'btn btn-sm btn-primary',
+        assert.strictEqual(form.$('button[name="1"]').attr('class'), 'btn btn-primary',
             "header buttons with bootstrap primary class should receive the correct classes");
-        assert.strictEqual(form.$('button[name="2"]').attr('class'), 'btn btn-sm btn-primary',
+        assert.strictEqual(form.$('button[name="2"]').attr('class'), 'btn btn-primary',
             "header buttons with oe_highlight class should receive the correct classes");
-        assert.strictEqual(form.$('button[name="3"]').attr('class'), 'btn btn-sm btn-default',
+        assert.strictEqual(form.$('button[name="3"]').attr('class'), 'btn btn-default',
             "header buttons with bootstrap default class should receive the correct classes");
-        assert.strictEqual(form.$('button[name="4"]').attr('class'), 'btn btn-sm btn-link',
+        assert.strictEqual(form.$('button[name="4"]').attr('class'), 'btn btn-link',
             "header buttons with bootstrap link class should receive the correct classes");
-        assert.strictEqual(form.$('button[name="5"]').attr('class'), 'btn btn-sm btn-link',
+        assert.strictEqual(form.$('button[name="5"]').attr('class'), 'btn btn-link',
             "header buttons with oe_link class should receive the correct classes");
-        assert.strictEqual(form.$('button[name="6"]').attr('class'), 'btn btn-sm btn-success',
+        assert.strictEqual(form.$('button[name="6"]').attr('class'), 'btn btn-success',
             "header buttons with bootstrap state class should receive the correct classes");
-        assert.strictEqual(form.$('button[name="7"]').attr('class'), 'btn btn-sm o_this_is_a_button btn-default',
+        assert.strictEqual(form.$('button[name="7"]').attr('class'), 'btn o_this_is_a_button btn-default',
             "header buttons with custom classes should receive the correct classes");
-        assert.strictEqual(form.$('button[name="8"]').attr('class'), 'btn btn-sm btn-default',
+        assert.strictEqual(form.$('button[name="8"]').attr('class'), 'btn btn-default',
             "sheet header buttons without any class should receive the correct classes");
-        assert.strictEqual(form.$('button[name="9"]').attr('class'), 'btn btn-sm btn-primary',
+        assert.strictEqual(form.$('button[name="9"]').attr('class'), 'btn btn-primary',
             "sheet buttons with bootstrap primary class should receive the correct classes");
-        assert.strictEqual(form.$('button[name="10"]').attr('class'), 'btn btn-sm btn-primary',
+        assert.strictEqual(form.$('button[name="10"]').attr('class'), 'btn btn-primary',
             "sheet buttons with oe_highlight class should receive the correct classes");
-        assert.strictEqual(form.$('button[name="11"]').attr('class'), 'btn btn-sm btn-default',
+        assert.strictEqual(form.$('button[name="11"]').attr('class'), 'btn btn-default',
             "sheet buttons with bootstrap default class should receive the correct classes");
-        assert.strictEqual(form.$('button[name="12"]').attr('class'), 'btn btn-sm btn-link',
+        assert.strictEqual(form.$('button[name="12"]').attr('class'), 'btn btn-link',
             "sheet buttons with bootstrap link class should receive the correct classes");
-        assert.strictEqual(form.$('button[name="13"]').attr('class'), 'btn btn-sm btn-link',
+        assert.strictEqual(form.$('button[name="13"]').attr('class'), 'btn btn-link',
             "sheet buttons with oe_link class should receive the correct classes");
-        assert.strictEqual(form.$('button[name="14"]').attr('class'), 'btn btn-sm btn-success',
+        assert.strictEqual(form.$('button[name="14"]').attr('class'), 'btn btn-success',
             "sheet buttons with bootstrap state class should receive the correct classes");
-        assert.strictEqual(form.$('button[name="15"]').attr('class'), 'btn btn-sm o_this_is_a_button',
+        assert.strictEqual(form.$('button[name="15"]').attr('class'), 'btn o_this_is_a_button',
             "sheet buttons with custom classes should receive the correct classes");
 
         form.destroy();
diff --git a/addons/web/static/tests/views/kanban_tests.js b/addons/web/static/tests/views/kanban_tests.js
index 1f7e2065638..bbf02b1eaae 100644
--- a/addons/web/static/tests/views/kanban_tests.js
+++ b/addons/web/static/tests/views/kanban_tests.js
@@ -2760,7 +2760,7 @@ QUnit.module('Views', {
                         '<t t-name="kanban-box">' +
                             '<div>' +
                                 '<field name="foo"/>' +
-                                '<button type="object" attrs="{\'invisible\':[\'|\', (\'bar\',\'=\',True), (\'category_ids\', \'!=\', [])]}" class="btn btn-primary pull-right btn-sm" name="channel_join_and_get_info">Join</button>' +
+                                '<button type="object" attrs="{\'invisible\':[\'|\', (\'bar\',\'=\',True), (\'category_ids\', \'!=\', [])]}" class="btn btn-primary pull-right" name="channel_join_and_get_info">Join</button>' +
                             '</div>' +
                         '</t>' +
                     '</templates>' +
diff --git a/addons/web/static/tests/views/view_dialogs_tests.js b/addons/web/static/tests/views/view_dialogs_tests.js
index 1e57474e4b5..293773dc01c 100644
--- a/addons/web/static/tests/views/view_dialogs_tests.js
+++ b/addons/web/static/tests/views/view_dialogs_tests.js
@@ -359,7 +359,7 @@ QUnit.module('Views', {
         assert.equal($modal.find('.o_data_cell').text(), 'Awsome',
             'There should be one item in the list of the modal');
 
-        $modal.find('.btn.btn-sm.btn-primary').click();
+        $modal.find('.btn.btn-primary').click();
 
         form.destroy();
     });
diff --git a/addons/web/views/database_manager.html b/addons/web/views/database_manager.html
index 11037f13d25..c555c9e2e88 100644
--- a/addons/web/views/database_manager.html
+++ b/addons/web/views/database_manager.html
@@ -150,13 +150,13 @@
         </div>
         {% if manage %}
         <div class="text-left">
-          <button type="button" data-toggle="modal" data-target=".o_database_create" class="btn btn-sm btn-primary">
+          <button type="button" data-toggle="modal" data-target=".o_database_create" class="btn btn-primary">
             Create Database
           </button>
-          <button type="button" data-toggle="modal" data-target=".o_database_restore" class="btn btn-sm btn-primary">
+          <button type="button" data-toggle="modal" data-target=".o_database_restore" class="btn btn-primary">
             Restore Database
           </button>
-          <button type="button" data-toggle="modal" data-target=".o_database_master" class="btn btn-sm btn-primary">
+          <button type="button" data-toggle="modal" data-target=".o_database_master" class="btn btn-primary">
             Set Master Password
           </button>
         </div>
diff --git a/addons/web_diagram/static/src/xml/base_diagram.xml b/addons/web_diagram/static/src/xml/base_diagram.xml
index c6eb76d7f40..3745e0a3838 100644
--- a/addons/web_diagram/static/src/xml/base_diagram.xml
+++ b/addons/web_diagram/static/src/xml/base_diagram.xml
@@ -2,7 +2,7 @@
 
 <t t-name="DiagramView.buttons">
 	<div t-if="widget.is_action_enabled('create')">
-        <button type="button" class="btn btn-primary btn-sm o_diagram_new_button">
+        <button type="button" class="btn btn-primary o_diagram_new_button">
             New Node
         </button>
     </div>
diff --git a/addons/web_editor/static/src/js/editor/rte.summernote.js b/addons/web_editor/static/src/js/editor/rte.summernote.js
index 0661d62dc30..b0669f4b390 100644
--- a/addons/web_editor/static/src/js/editor/rte.summernote.js
+++ b/addons/web_editor/static/src/js/editor/rte.summernote.js
@@ -168,7 +168,7 @@ renderer.tplPopovers = function (lang, options) {
 
     var $alt = $('<div class="btn-group"/>');
     $alt.appendTo($imagePopover.find('.popover-content'));
-    $alt.append('<button class="btn btn-default btn-sm btn-small" data-event="alt"><strong>' + _t('Description') + ': </strong><span class="o_image_alt"/></button>');
+    $alt.append('<button class="btn btn-default" data-event="alt"><strong>' + _t('Description') + ': </strong><span class="o_image_alt"/></button>');
 
     //////////////// link popover
 
diff --git a/addons/web_editor/static/src/js/editor/snippets.editor.js b/addons/web_editor/static/src/js/editor/snippets.editor.js
index d03e7a4a03d..97bd73cb832 100644
--- a/addons/web_editor/static/src/js/editor/snippets.editor.js
+++ b/addons/web_editor/static/src/js/editor/snippets.editor.js
@@ -1052,7 +1052,7 @@ var SnippetsMenu = Widget.extend({
                 if (moduleID) {
                     $snippet.addClass('o_snippet_install');
                     var $installBtn = $('<a/>', {
-                        class: 'btn btn-primary btn-sm o_install_btn',
+                        class: 'btn btn-primary o_install_btn',
                         target: '_blank',
                         href: '/web#id=' + moduleID + '&view_type=form&model=ir.module.module&action=base.open_module_tree',
                         text: _t("Install"),
diff --git a/addons/web_editor/static/src/xml/ace.xml b/addons/web_editor/static/src/xml/ace.xml
index b65af78b3dc..4380a73ae54 100644
--- a/addons/web_editor/static/src/xml/ace.xml
+++ b/addons/web_editor/static/src/xml/ace.xml
@@ -5,7 +5,7 @@
     <div class="o_ace_view_editor">
         <div class="form-inline o_ace_view_editor_title">
             <div class="btn-group o_ace_type_switcher">
-                <button type="button" class="btn btn-sm btn-info dropdown-toggle" data-toggle="dropdown">XML (HTML)</button>
+                <button type="button" class="btn btn-info dropdown-toggle" data-toggle="dropdown">XML (HTML)</button>
                 <ul class="dropdown-menu" role="menu">
                     <li><a role="menuitem" href="#" class="o_ace_type_switcher_choice" data-type="xml">XML (HTML)</a></li>
                     <li><a role="menuitem" href="#" class="o_ace_type_switcher_choice" data-type="scss">SCSS (CSS)</a></li>
@@ -26,8 +26,8 @@
                 Include All SCSS Files
             </label>
             <div class="o_button_section">
-                <button data-action="save" type="submit" class="btn btn-sm btn-primary">Save</button>
-                <button data-action="close" type="button" class="btn btn-sm btn-default">Close</button>
+                <button data-action="save" type="submit" class="btn btn-primary">Save</button>
+                <button data-action="close" type="button" class="btn btn-default">Close</button>
             </div>
         </div>
         <div id="ace-view-id">
diff --git a/addons/web_editor/static/src/xml/backend.xml b/addons/web_editor/static/src/xml/backend.xml
index 40be4f05d07..76663cc9fbc 100644
--- a/addons/web_editor/static/src/xml/backend.xml
+++ b/addons/web_editor/static/src/xml/backend.xml
@@ -9,7 +9,7 @@
 
     <t t-name="web_editor.FieldTextHtml.button.translate">
         <div class="btn-group pull-right">
-            <button t-if="widget.field.translate" class="o_field_translate btn btn-default btn-sm btn-small" style="height: 24px; padding: 1px 17px 0px 5px" aria-label="Translate" title="Translate">
+            <button t-if="widget.field.translate" class="o_field_translate btn btn-default" style="height: 24px; padding: 1px 17px 0px 5px" aria-label="Translate" title="Translate">
                 <span class="fa fa-language fa-lg oe_input_icon"/>
             </button>
         </div>
diff --git a/addons/web_editor/static/src/xml/editor.xml b/addons/web_editor/static/src/xml/editor.xml
index f4a34c5ab4b..01a4af11ac4 100644
--- a/addons/web_editor/static/src/xml/editor.xml
+++ b/addons/web_editor/static/src/xml/editor.xml
@@ -9,8 +9,8 @@
         <div id="web_editor-top-edit">
             <div id="web_editor-toolbars"/>
             <form class="navbar-form text-muted">
-                <button type="button" class="btn btn-sm btn-default" data-action="cancel"><i class="fa fa-times"/> Discard</button>
-                <button type="button" class="btn btn-sm btn-primary" data-action="save"><i class="fa fa-floppy-o"/> Save</button>
+                <button type="button" class="btn btn-default" data-action="cancel"><i class="fa fa-times"/> Discard</button>
+                <button type="button" class="btn btn-primary" data-action="save"><i class="fa fa-floppy-o"/> Save</button>
             </form>
         </div>
     </t>
diff --git a/addons/web_editor/static/src/xml/snippets.xml b/addons/web_editor/static/src/xml/snippets.xml
index 361a5780b4d..3c368ebaaf2 100644
--- a/addons/web_editor/static/src/xml/snippets.xml
+++ b/addons/web_editor/static/src/xml/snippets.xml
@@ -10,14 +10,14 @@
             </div>
             <div class="oe_overlay_options" contentEditable="false">
                 <div class="btn-group">
-                    <a role="button" href="#" class="btn btn-default btn-sm oe_snippet_parent" title="Select Parent Container" aria-label="Select Parent Container"><i class="fa fa-lg fa-level-up"/></a>
+                    <a role="button" href="#" class="btn btn-default oe_snippet_parent" title="Select Parent Container" aria-label="Select Parent Container"><i class="fa fa-lg fa-level-up"/></a>
                     <div class="dropdown oe_options d-none btn-group">
-                        <a role="button" href="#" data-toggle="dropdown" class="btn btn-primary btn-sm" title="Customize">Customize</a>
+                        <a role="button" href="#" data-toggle="dropdown" class="btn btn-primary" title="Customize">Customize</a>
                         <ul class="dropdown-menu" role="menu"/>
                     </div>
-                    <a role="button" href="#" class="btn btn-default btn-sm oe_snippet_move" title="Drag to Move" aria-label="Drag to Move"><i class="fa fa-arrows ml4 mr4"></i></a>
-                    <a role="button" href="#" class="btn btn-default btn-sm oe_snippet_clone" title="Duplicate Container" aria-label="Duplicate Container"><i class="fa fa-files-o ml4 mr4"></i></a>
-                    <a role="button" href="#" class="btn btn-default btn-sm oe_snippet_remove" title="Remove Block" aria-label="Remove Block"><i class="fa fa-trash-o ml4 mr4"></i></a>
+                    <a role="button" href="#" class="btn btn-default oe_snippet_move" title="Drag to Move" aria-label="Drag to Move"><i class="fa fa-arrows ml4 mr4"></i></a>
+                    <a role="button" href="#" class="btn btn-default oe_snippet_clone" title="Duplicate Container" aria-label="Duplicate Container"><i class="fa fa-files-o ml4 mr4"></i></a>
+                    <a role="button" href="#" class="btn btn-default oe_snippet_remove" title="Remove Block" aria-label="Remove Block"><i class="fa fa-trash-o ml4 mr4"></i></a>
                 </div>
             </div>
         </div>
@@ -40,7 +40,7 @@
     <!-- t-field options -->
     <t t-name="web_editor.many2one.button">
         <div class="btn-group">
-            <a role="button" href="#" class="btn btn-default btn-sm dropdown-toggle" data-toggle="dropdown" data-hover="dropdown" title="Search Contact" aria-label="Search Contact"><i class="fa fa-search"></i></a>
+            <a role="button" href="#" class="btn btn-default dropdown-toggle" data-toggle="dropdown" data-hover="dropdown" title="Search Contact" aria-label="Search Contact"><i class="fa fa-search"></i></a>
             <ul class="dropdown-menu contact_menu" role="menu">
                 <li><a role="menuitem"><input href="#" type="email" placeholder="Search"/></a></li>
             </ul>
diff --git a/addons/web_tour/static/src/xml/debug_manager.xml b/addons/web_tour/static/src/xml/debug_manager.xml
index 11c259e9944..6077723cf27 100644
--- a/addons/web_tour/static/src/xml/debug_manager.xml
+++ b/addons/web_tour/static/src/xml/debug_manager.xml
@@ -26,7 +26,7 @@
             <tr t-foreach="tours" t-as="tour">
                 <td><t t-esc="tour"/></td>
                 <td><t t-esc="tours[tour].url"/></td>
-                <td><button type="button" class="btn btn-sm btn-primary fa fa-play o_start_tour" t-att-data-name="tour" aria-label="Tour" title="Tour"/></td>
+                <td><button type="button" class="btn btn-primary fa fa-play o_start_tour" t-att-data-name="tour" aria-label="Tour" title="Tour"/></td>
             </tr>
         </table>
     </div>
diff --git a/addons/website/static/src/xml/website.backend.xml b/addons/website/static/src/xml/website.backend.xml
index e01d53482b6..1bf996f7cef 100644
--- a/addons/website/static/src/xml/website.backend.xml
+++ b/addons/website/static/src/xml/website.backend.xml
@@ -33,7 +33,7 @@
                             </div>
                             <div class="o_buttons text-center">
                                 <h3>There is no data currently available.</h3>
-                                <button class="btn btn-sm btn-primary js_link_analytics_settings center-block mb8">Link my Analytics Account</button>
+                                <button class="btn btn-primary js_link_analytics_settings center-block mb8">Link my Analytics Account</button>
                             </div>
                         </div>
                     </div>
@@ -62,10 +62,10 @@
 
     <t t-name="website.DateRangeButtons">
         <!-- TODO: Hide in mobile as it is going to push in control panel and it breaks UI, maybe we will improve it in future -->
-        <div class="btn-group btn-group-sm o_date_range_buttons d-none d-md-inline-flex pull-right">
-            <button class="btn btn-sm btn-default js_date_range active" data-date="week">Last Week</button>
-            <button class="btn btn-sm btn-default js_date_range" data-date="month">Last Month</button>
-            <button class="btn btn-sm btn-default js_date_range" data-date="year">Last Year</button>
+        <div class="btn-group o_date_range_buttons d-none d-md-inline-flex pull-right">
+            <button class="btn btn-default js_date_range active" data-date="week">Last Week</button>
+            <button class="btn btn-default js_date_range" data-date="month">Last Month</button>
+            <button class="btn btn-default js_date_range" data-date="year">Last Year</button>
         </div>
     </t>
 
diff --git a/addons/website/static/src/xml/website.xml b/addons/website/static/src/xml/website.xml
index bdd5aa42941..7bded7ce4e6 100644
--- a/addons/website/static/src/xml/website.xml
+++ b/addons/website/static/src/xml/website.xml
@@ -23,8 +23,8 @@
                         </form>
                     </main>
                     <footer class="modal-footer">
-                        <button type="button" class="btn btn-sm btn-primary btn-continue">Continue</button>
-                        <button type="button" class="btn btn-sm btn-default" data-dismiss="modal" aria-label="Cancel">Cancel</button>
+                        <button type="button" class="btn btn-primary btn-continue">Continue</button>
+                        <button type="button" class="btn btn-default" data-dismiss="modal" aria-label="Cancel">Cancel</button>
                     </footer>
                 </div>
             </div>
diff --git a/addons/website/views/website_templates.xml b/addons/website/views/website_templates.xml
index cbc754b99f1..421157ea2b4 100644
--- a/addons/website/views/website_templates.xml
+++ b/addons/website/views/website_templates.xml
@@ -310,7 +310,7 @@
     <ul class="js_language_selector mb0 list-inline" t-if="(request and request.is_frontend_multilang and len(languages) &gt; 1) or (website and (editable or translatable))">
         <li>
             <div class="dropup">
-                <button class="btn btn-sm btn-default dropdown-toggle" type="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="true">
+                <button class="btn btn-default dropdown-toggle" type="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="true">
                     <span t-esc="list(filter(lambda lg : lg[0] == lang, languages))[0][1].split('/').pop()"/>
                     <span class="caret ml4"/>
                 </button>
diff --git a/addons/website_blog/static/src/js/website.tour.blog.js b/addons/website_blog/static/src/js/website.tour.blog.js
index f42f21142a1..d1afa46f217 100644
--- a/addons/website_blog/static/src/js/website.tour.blog.js
+++ b/addons/website_blog/static/src/js/website.tour.blog.js
@@ -21,7 +21,7 @@ odoo.define("website_blog.tour", function (require) {
         position: "top",
         run: "text",
     }, {
-        trigger: "#oe_manipulators .oe_overlay.oe_active a.btn.btn-primary.btn-sm",
+        trigger: "#oe_manipulators .oe_overlay.oe_active a.btn.btn-primary",
         extra_trigger: "#wrap h1[data-oe-expression=\"blog_post.name\"]:not(:containsExact(\"\"))",
         content: _t("Set a blog post <b>cover</b>."),
         position: "bottom",
diff --git a/addons/website_crm_partner_assign/views/website_crm_partner_assign_templates.xml b/addons/website_crm_partner_assign/views/website_crm_partner_assign_templates.xml
index fbbc312a1ae..c0645d9ebe9 100644
--- a/addons/website_crm_partner_assign/views/website_crm_partner_assign_templates.xml
+++ b/addons/website_crm_partner_assign/views/website_crm_partner_assign_templates.xml
@@ -510,7 +510,7 @@
                             </h4>
                             <span class="btn-group pull-right" role="group">
                                 <t t-foreach="stages" t-as="stage">
-                                    <button type="button" t-att-data="stage.id" t-att-opp="opportunity.id" t-attf-class="pull-right btn btn-sm opp-stage-button #{'btn-default' if opportunity.stage_id.name != stage.name else 'disabled btn-primary'}">
+                                    <button type="button" t-att-data="stage.id" t-att-opp="opportunity.id" t-attf-class="pull-right btn opp-stage-button #{'btn-default' if opportunity.stage_id.name != stage.name else 'disabled btn-primary'}">
                                         <span t-field="stage.name"/>
                                     </button>
                                 </t>
@@ -536,7 +536,7 @@
                 <div class="panel-body">
                     <div class="col-md-6">
                         <div>
-                            <button type="button" data-toggle="modal" data-target=".modal_edit_contact" class="btn btn-sm btn-primary" style="margin-bottom: 10px;">Edit Contact</button>
+                            <button type="button" data-toggle="modal" data-target=".modal_edit_contact" class="btn btn-primary" style="margin-bottom: 10px;">Edit Contact</button>
                             <div role="dialog" class="modal fade modal_edit_contact">
                                 <div class="modal-dialog">
                                     <form method="POST" class="js_accept_json modal-content js_website_submit_form edit_contact_form">
@@ -651,7 +651,7 @@
                     </div>
                     <div class="col-md-6">
                         <div>
-                            <button type="button" data-toggle="modal" data-target=".modal_edit_opp" class="btn btn-sm btn-primary" style="margin-bottom: 10px;">Edit Opportunity</button>
+                            <button type="button" data-toggle="modal" data-target=".modal_edit_opp" class="btn btn-primary" style="margin-bottom: 10px;">Edit Opportunity</button>
                             <div role="dialog" class="modal fade modal_edit_opp">
                                 <div class="modal-dialog">
                                     <form method="POST" class="js_accept_json modal-content js_website_submit_form edit_opp_form">
diff --git a/addons/website_sale/static/src/xml/website_sale.xml b/addons/website_sale/static/src/xml/website_sale.xml
index 6db148e8643..04b224c10d2 100644
--- a/addons/website_sale/static/src/xml/website_sale.xml
+++ b/addons/website_sale/static/src/xml/website_sale.xml
@@ -9,7 +9,7 @@
                     <span><t t-esc="title"/></span>
                     <table class="change_statement_name_container oe_form o_form"><tr>
                         <td><input class="change_statement_name_field" type="text"/></td>
-                        <td><button class="change_statement_name_button btn btn-primary btn-sm">OK</button></td>
+                        <td><button class="change_statement_name_button btn btn-primary">OK</button></td>
                     </tr></table>
                 </h1>
             </t>
diff --git a/addons/website_sale/views/templates.xml b/addons/website_sale/views/templates.xml
index 76331278456..4fae02ef552 100644
--- a/addons/website_sale/views/templates.xml
+++ b/addons/website_sale/views/templates.xml
@@ -1458,7 +1458,7 @@
                                 </div>
                                 <t t-if="request.env['ir.config_parameter'].sudo().get_param('auth_signup.invitation_scope', 'b2b') == 'b2c' and request.website.is_public_user()">
                                     <p class='alert alert-info mt16' role="status">
-                                        <a role="button" t-att-href='order.partner_id.signup_prepare() and order.partner_id.signup_url' class='btn btn-sm btn-primary'>Sign Up</a>
+                                        <a role="button" t-att-href='order.partner_id.signup_prepare() and order.partner_id.signup_url' class='btn btn-primary'>Sign Up</a>
                                          to follow your order.
                                     </p>
                                 </t>
diff --git a/addons/website_sale_link_tracker/static/src/xml/website_sale_dashboard_utm_chart.xml b/addons/website_sale_link_tracker/static/src/xml/website_sale_dashboard_utm_chart.xml
index c56cb4549ce..acd9ee9651d 100644
--- a/addons/website_sale_link_tracker/static/src/xml/website_sale_dashboard_utm_chart.xml
+++ b/addons/website_sale_link_tracker/static/src/xml/website_sale_dashboard_utm_chart.xml
@@ -20,7 +20,7 @@
 
     <t t-name="website_sale.LinkTrackersDropDown">
         <div class="dropdown">
-            <button class="btn btn-default btn-sm dropdown-toggle utm_dropdown ml4" id="utm_dropdown" type="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="true"><span class="utm_button_name">Campaigns</span><span class="caret ml4"/>
+            <button class="btn btn-default dropdown-toggle utm_dropdown ml4" id="utm_dropdown" type="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="true"><span class="utm_button_name">Campaigns</span><span class="caret ml4"/>
             </button>
             <ul class="dropdown-menu" role="menu" aria-labelledby="utm_dropdown">
                 <li><a role="menuitem" class="js_utm_selector" name="campaign_id">Campaigns</a></li>
diff --git a/addons/website_sale_options/views/website_sale_options_templates.xml b/addons/website_sale_options/views/website_sale_options_templates.xml
index 0814ea3218b..53dede7d207 100644
--- a/addons/website_sale_options/views/website_sale_options_templates.xml
+++ b/addons/website_sale_options/views/website_sale_options_templates.xml
@@ -121,7 +121,7 @@
 
                   <div class='mt8'>
                     <input type="hidden" class="js_optional_same_quantity" t-attf-name="optional-add-#{product_index}" value="0"/>
-                    <a role="button" href="#" class="js_add btn btn-sm btn-info"><strong>Add<span class='d-none d-md-inline'> to Cart</span></strong></a>
+                    <a role="button" href="#" class="js_add btn btn-info"><strong>Add<span class='d-none d-md-inline'> to Cart</span></strong></a>
                     <span class="js_remove d-none">
                       <span class="js_item">1 </span><span class="js_items d-none">5 </span> <span t-field="product.uom_id.sudo().name"/><br/>
                       <a role="button" href="#" class="js_remove btn btn-xs btn-info"><small>Remove <span class='d-none d-md-inline'> from Cart</span></small></a>
diff --git a/odoo/addons/base/views/ir_module_views.xml b/odoo/addons/base/views/ir_module_views.xml
index 9ca6a61f441..99fdf5b91eb 100644
--- a/odoo/addons/base/views/ir_module_views.xml
+++ b/odoo/addons/base/views/ir_module_views.xml
@@ -165,7 +165,7 @@
                           </p>
                           <div class="oe_module_action">
                             <code groups="base.group_no_one"><small><field name="name"/></small></code>
-                            <button type="object" class="btn btn-primary pull-right btn-sm" name="button_immediate_install" states="uninstalled">Install</button>
+                            <button type="object" class="btn btn-primary pull-right" name="button_immediate_install" states="uninstalled">Install</button>
                             <span t-if="installed" class="pull-right text-muted mr8">Installed</span>
                           </div>
                         </div>
diff --git a/odoo/addons/base/views/res_partner_views.xml b/odoo/addons/base/views/res_partner_views.xml
index c565a89668a..9a694dc1ab0 100644
--- a/odoo/addons/base/views/res_partner_views.xml
+++ b/odoo/addons/base/views/res_partner_views.xml
@@ -146,7 +146,7 @@
                                 domain="[('is_company', '=', True)]" context="{'default_is_company': True, 'default_supplier': supplier, 'default_customer': customer}"
                                 attrs="{'invisible': ['|', '&amp;', ('is_company','=', True),('parent_id', '=', False),('company_name', '!=', False),('company_name', '!=', '')]}"/>
                                 <field name="company_name" attrs="{'invisible': ['|', '|', ('company_name', '=', False), ('company_name', '=', ''), ('is_company', '=', True)]}"/>
-                                <button name="create_company" type="object" string="Create company" class="btn btn-sm oe_edit_only fa fa-external-link btn btn-link " attrs="{'invisible': ['|', '|', ('is_company','=', True), ('company_name', '=', ''), ('company_name', '=', False)]}"/>
+                                <button name="create_company" type="object" string="Create company" class="oe_edit_only fa fa-external-link btn-link " attrs="{'invisible': ['|', '|', ('is_company','=', True), ('company_name', '=', ''), ('company_name', '=', False)]}"/>
                         </div>
                     </div>
                     <group>
@@ -218,7 +218,7 @@
                                 domain="[('is_company', '=', True)]" context="{'default_is_company': True, 'default_supplier': supplier, 'default_customer': customer}"
                                 attrs="{'invisible': ['|', '&amp;', ('is_company','=', True),('parent_id', '=', False),('company_name', '!=', False),('company_name', '!=', '')]}"/>
                                 <field name="company_name" attrs="{'invisible': ['|', '|', ('company_name', '=', False), ('company_name', '=', ''), ('is_company', '=', True)]}"/>
-                                <button name="create_company" type="object" string="Create company" class="btn btn-sm oe_edit_only fa fa-external-link btn btn-link " attrs="{'invisible': ['|', '|', ('is_company','=', True), ('company_name', '=', ''), ('company_name', '=', False)]}"/>
+                                <button name="create_company" type="object" string="Create company" class="oe_edit_only fa fa-external-link btn-link" attrs="{'invisible': ['|', '|', ('is_company','=', True), ('company_name', '=', ''), ('company_name', '=', False)]}"/>
                         </div>
                     </div>