diff --git a/addons/account_payment/views/account_portal_templates.xml b/addons/account_payment/views/account_portal_templates.xml
index ed222c82aee..a48dff7333c 100644
--- a/addons/account_payment/views/account_portal_templates.xml
+++ b/addons/account_payment/views/account_portal_templates.xml
@@ -66,10 +66,10 @@
         <xpath expr="//t[@t-call='portal.portal_record_sidebar']//div[hasclass('o_download_pdf')]" position="before">
             <t t-set="tx_ids" t-value="invoice.transaction_ids.filtered(lambda tx: tx.state in ('pending', 'authorized', 'done'))"/>
             <t t-set="pending_manual_txs" t-value="tx_ids.filtered(lambda tx: tx.state == 'pending' and tx.provider in ('none', 'transfer'))"/>
-            <div>
+            <div class="d-grid">
                 <a href="#" t-if="invoice.state == 'posted' and invoice.payment_state in ('not_paid', 'partial') and invoice.amount_total and invoice.move_type == 'out_invoice' and (pending_manual_txs or not tx_ids or invoice.amount_paid &lt; invoice.amount_total)"
 
-                    class="btn btn-primary btn-block mb-2" data-toggle="modal" data-target="#pay_with">
+                    class="btn btn-primary mb-2" data-toggle="modal" data-target="#pay_with">
                     <i class="fa fa-fw fa-arrow-circle-right"/> Pay Now
                 </a>
                 <div t-if="tx_ids and not pending_manual_txs and not invoice.amount_residual and invoice.payment_state not in ('paid', 'in_payment')" class="alert alert-info py-1 mb-2" >
diff --git a/addons/auth_signup/views/auth_signup_login_templates.xml b/addons/auth_signup/views/auth_signup_login_templates.xml
index 390982beccb..5c00f9e70f9 100644
--- a/addons/auth_signup/views/auth_signup_login_templates.xml
+++ b/addons/auth_signup/views/auth_signup_login_templates.xml
@@ -50,8 +50,8 @@
                     </p>
                     <input type="hidden" name="redirect" t-att-value="redirect"/>
                     <input type="hidden" name="token" t-att-value="token"/>
-                    <div class="text-center oe_login_buttons pt-3">
-                        <button type="submit" class="btn btn-primary btn-block"> Sign up</button>
+                    <div class="text-center oe_login_buttons d-grid pt-3">
+                        <button type="submit" class="btn btn-primary"> Sign up</button>
                         <a t-attf-href="/web/login?{{ keep_query() }}" class="btn btn-link btn-sm" role="button">Already have an account?</a>
                         <div class="o_login_auth"/>
                     </div>
@@ -90,8 +90,8 @@
                     </p>
                     <input type="hidden" name="redirect" t-att-value="redirect"/>
                     <input type="hidden" name="token" t-att-value="token"/>
-                    <div class="clearfix oe_login_buttons">
-                        <button type="submit" class="btn btn-primary btn-block">Reset Password</button>
+                    <div class="clearfix oe_login_buttons d-grid mt-3">
+                        <button type="submit" class="btn btn-primary">Reset Password</button>
                         <div class="d-flex justify-content-between align-items-center small mt-2">
                             <a t-if="not token" t-attf-href="/web/login?{{ keep_query() }}">Back to Login</a>
                             <a t-if="invalid_token" href="/web/login">Back to Login</a>
diff --git a/addons/auth_totp/views/templates.xml b/addons/auth_totp/views/templates.xml
index a9f60a58daf..d5c6a12ea28 100644
--- a/addons/auth_totp/views/templates.xml
+++ b/addons/auth_totp/views/templates.xml
@@ -27,8 +27,8 @@
                         <input type="checkbox" name="remember" id="switch-remember" value="1"/>
                         <label for="switch-remember">Don't ask again on this device</label>
                     </div>
-                        <div t-attf-class="clearfix oe_login_buttons text-center mb-1">
-                            <button type="submit" class="btn btn-primary btn-block">
+                        <div t-attf-class="clearfix oe_login_buttons text-center d-grid mb-1">
+                            <button type="submit" class="btn btn-primary">
                                 Login
                             </button>
                         </div>
diff --git a/addons/mail/static/src/xml/web_kanban_activity.xml b/addons/mail/static/src/xml/web_kanban_activity.xml
index a1a8929756b..cdfeee8323c 100644
--- a/addons/mail/static/src/xml/web_kanban_activity.xml
+++ b/addons/mail/static/src/xml/web_kanban_activity.xml
@@ -52,8 +52,8 @@
         </ul>
     </div>
     <div class="dropdown-divider m-0"/>
-    <div role="menuitem" class="o_schedule_activity dropdown-header p-0 text-center">
-        <button class="btn btn-secondary btn-block p-3">
+    <div role="menuitem" class="o_schedule_activity d-grid dropdown-header p-0 text-center">
+        <button class="btn btn-secondary p-3">
             <i class="fa fa-plus fa-fw"></i><strong>Schedule an activity</strong>
         </button>
     </div>
diff --git a/addons/note/static/src/xml/systray.xml b/addons/note/static/src/xml/systray.xml
index 96080f6f1c8..a4cb6beecac 100644
--- a/addons/note/static/src/xml/systray.xml
+++ b/addons/note/static/src/xml/systray.xml
@@ -2,8 +2,8 @@
 <templates>
     <t t-extend="mail.systray.ActivityMenu.Previews">
         <t t-jquery="t[t-foreach*='activities'][t-as*='activity']" t-operation="after">
-            <div class="o_note_show">
-                <a role="button" class="btn btn-block text-center">Add new note</a>
+            <div class="o_note_show d-grid">
+                <a role="button" class="btn text-center">Add new note</a>
             </div>
             <div class="o_note o_mail_preview d-none">
                 <div class="o_mail_preview_image o_mail_preview_app">
diff --git a/addons/web_editor/static/src/js/backend/convert_inline.js b/addons/web_editor/static/src/js/backend/convert_inline.js
index b1978df7b19..31316c5def4 100644
--- a/addons/web_editor/static/src/js/backend/convert_inline.js
+++ b/addons/web_editor/static/src/js/backend/convert_inline.js
@@ -1187,7 +1187,7 @@ function _getMatchedCSSRules(node, cssRules) {
         }
     };
 
-    if (processedStyle.display === 'block' && !(node.classList && node.classList.contains('btn-block'))) {
+    if (processedStyle.display === 'block') {
         delete processedStyle.display;
     }
     if (!processedStyle['box-sizing']) {
diff --git a/addons/web_editor/static/tests/convert_inline_tests.js b/addons/web_editor/static/tests/convert_inline_tests.js
index b2f7564d307..d1769e2606b 100644
--- a/addons/web_editor/static/tests/convert_inline_tests.js
+++ b/addons/web_editor/static/tests/convert_inline_tests.js
@@ -766,7 +766,7 @@ QUnit.module('convert_inline', {}, function () {
         $styleSheet.remove();
     });
     QUnit.test('remove unsupported styles', async function (assert) {
-        assert.expect(10);
+        assert.expect(9);
 
         const $styleSheet = $('<style type="text/css" title="test-stylesheet"/>');
         document.head.appendChild($styleSheet[0])
@@ -804,7 +804,7 @@ QUnit.module('convert_inline', {}, function () {
             "should have removed border initial");
         styleSheet.deleteRule(0);
 
-        // display: block (except for .btn-block)
+        // display: block
         styleSheet.insertRule(`
             .test-block {
                 display: block;
@@ -815,11 +815,6 @@ QUnit.module('convert_inline', {}, function () {
         assert.strictEqual($editable.html(),
             `<div class="test-block" style="box-sizing:border-box;"></div>`,
             "should have removed display block");
-        $editable = $(`<div>${`<div class="btn-block"></div>`}</div>`);
-        convertInline.classToStyle($editable, convertInline.getCSSRules($editable[0].ownerDocument));
-        assert.strictEqual($editable.html(),
-            `<div class="btn-block" style="box-sizing:border-box;width:100%;display:block;" width="100%"></div>`,
-            "should not have removed display block for .btn-block");
         styleSheet.deleteRule(0);
 
         // !important
diff --git a/addons/website_event_booth/views/event_booth_registration_templates.xml b/addons/website_event_booth/views/event_booth_registration_templates.xml
index ce6b05e3fd3..fc57879cf9d 100644
--- a/addons/website_event_booth/views/event_booth_registration_templates.xml
+++ b/addons/website_event_booth/views/event_booth_registration_templates.xml
@@ -54,8 +54,8 @@
                     <span class="o_wbooth_registration_error_message"/>
                 </div>
                 <div class="form-group">
-                    <div class="col-sm-6 offset-sm-3 mt-5">
-                        <button type="submit" class="btn btn-primary btn-block font-weight-bold o_wbooth_registration_confirm">
+                    <div class="d-grid col-sm-6 offset-sm-3 mt-5">
+                        <button type="submit" class="btn btn-primary font-weight-bold o_wbooth_registration_confirm">
                             Book my Booths
                         </button>
                     </div>
diff --git a/addons/website_sale_comparison/static/src/xml/comparison.xml b/addons/website_sale_comparison/static/src/xml/comparison.xml
index a4ae2bb6071..5ef256d69d6 100644
--- a/addons/website_sale_comparison/static/src/xml/comparison.xml
+++ b/addons/website_sale_comparison/static/src/xml/comparison.xml
@@ -17,7 +17,7 @@
                         </div>
                     </div>
                     <div class="o_comparelist_button" style='display:none'>
-                        <a role="button" class="btn btn-primary btn-block" href="#"><i class="fa fa-exchange mr-2"/>Compare</a>
+                        <a role="button" class="btn btn-primary d-block" href="#"><i class="fa fa-exchange mr-2"/>Compare</a>
                     </div>
                 </span>
             </span>
diff --git a/addons/website_sale_comparison/views/website_sale_comparison_template.xml b/addons/website_sale_comparison/views/website_sale_comparison_template.xml
index 895e0dc0948..a1fb3dbab63 100644
--- a/addons/website_sale_comparison/views/website_sale_comparison_template.xml
+++ b/addons/website_sale_comparison/views/website_sale_comparison_template.xml
@@ -126,7 +126,7 @@
                                             <input type="hidden" name="csrf_token" t-att-value="request.csrf_token()" />
                                                 <input name="product_id" t-att-value="product.id" type="hidden"
                                                        t-att-data-product-tracking-info="json.dumps(request.env['product.template'].get_google_analytics_data(combination_info))"/>
-                                                <a role="button" class="btn btn-primary btn-block a-submit" href="#"><i class="fa fa-shopping-cart mr-2"></i>Add to Cart</a>
+                                                <a role="button" class="btn btn-primary d-block a-submit" href="#"><i class="fa fa-shopping-cart mr-2"></i>Add to Cart</a>
                                             </form>
                                         </div>
                                     </td>
diff --git a/addons/website_sale_slides/views/website_slides_templates.xml b/addons/website_sale_slides/views/website_slides_templates.xml
index 534f61fc591..1bb4d2541c8 100644
--- a/addons/website_sale_slides/views/website_slides_templates.xml
+++ b/addons/website_sale_slides/views/website_slides_templates.xml
@@ -121,7 +121,7 @@
                     <input type="hidden" name="csrf_token" t-att-value="request.csrf_token()" />
                     <input type="hidden" class="product_id" name="product_id" t-att-value="channel.product_id.id"/>
                     <a id="add_to_cart" role="button" href="#"
-                       class="btn btn-primary btn-block js_check_product o_js_add_to_cart a-submit"
+                       class="btn btn-primary d-block js_check_product o_js_add_to_cart a-submit"
                        data-animation-selector=".o_wslides_course_pict">
                         <i class="fa fa-shopping-cart"></i> Add to Cart
                     </a>
diff --git a/addons/website_slides/views/website_slides_templates_course.xml b/addons/website_slides/views/website_slides_templates_course.xml
index 4b8fe498700..67cff2ece4a 100644
--- a/addons/website_slides/views/website_slides_templates_course.xml
+++ b/addons/website_slides/views/website_slides_templates_course.xml
@@ -280,8 +280,8 @@
                 </tr>
             </table>
 
-            <div class="mt-3 o_not_editable">
-                <button role="button" class="btn btn-link btn-block" title="Share Channel"
+            <div class="mt-3 d-grid o_not_editable">
+                <button role="button" class="btn btn-link" title="Share Channel"
                     aria-label="Share Channel"
                     data-toggle="modal" t-att-data-target="'#slideChannelShareModal_%s' % channel.id">
                     <i class="fa fa-share-square fa-fw"/> Share
@@ -292,9 +292,9 @@
 </template>
 
 <template id="course_join">
-    <div class="o_wslides_js_course_join flex-grow-1">
+    <div class="o_wslides_js_course_join flex-grow-1 d-grid">
         <a t-if="not channel.is_member and channel.enroll == 'public'" role="button"
-            class="btn btn-primary btn-block o_wslides_js_course_join_link"
+            class="btn btn-primary o_wslides_js_course_join_link"
             title="Start Course" aria-label="Start Course Channel"
             t-att-href="'#'"
             t-att-data-channel-id="channel.id"