diff --git a/addons/website/views/views.xml b/addons/website/views/views.xml
index d3bda075b37..ee2b6b4f52e 100644
--- a/addons/website/views/views.xml
+++ b/addons/website/views/views.xml
@@ -394,8 +394,8 @@
 
         <template id="publish">
             <a href="#" t-att-data-id="object.id" t-att-data-object="object._name" class="pull-right" t-if="editable" t-ignore="true">
-                <span t-att-class="'label label-success js_unpublish %%s' %% (not object.website_published and 'hidden' or '')">Unpublish</span>
-                <span t-att-class="'label label-important js_publish %%s' %% (object.website_published and 'hidden' or '')">Publish</span>
+                <span t-attf-class="label label-success js_unpublish #{ '' if object.website_published else 'hidden' }">Unpublish</span>
+                <span t-attf-class="label label-important js_publish #{ 'hidden' if object.website_published else '' }">Publish</span>
             </a>
         </template>
 
diff --git a/addons/website_event/views/website_event.xml b/addons/website_event/views/website_event.xml
index 4ccd0c31948..7c05419d15a 100644
--- a/addons/website_event/views/website_event.xml
+++ b/addons/website_event/views/website_event.xml
@@ -29,7 +29,7 @@
                             <li class="nav-header">Date</li>
                             <t t-foreach="dates" t-as="date">
                                 <li t-att-class="searches.get('date') == date[0] and 'active' or ''">
-                                    <a  t-att-href="'/event/%%s&amp;date=%%s' %% (search_path, date[0])"><t t-esc="date[1]"/> <small t-if="date[3]">(<t t-esc="date[3]"/>)</small></a>
+                                    <a t-attf-href="/event/#{ search_path }&amp;date=#{ date[0] }"><t t-esc="date[1]"/> <small t-if="date[3]">(<t t-esc="date[3]"/>)</small></a>
                                 </li>
                             </t>
                         </ul>
@@ -49,7 +49,7 @@
                                     <t t-if="event.event_ticket_ids">
                                         <span t-if="event.register_avail == 9999" class="label pull-right label-info">Tickets availables.</span>
                                         <span t-if="not event.register_avail" class="label pull-right">No ticket available.</span>
-                                        <span t-if="event.register_avail and event.register_avail != 9999" t-att-class="'label pull-right label-%%s' %% (event.register_avail &lt;= 10 and 'warning' or 'info')">
+                                        <span t-if="event.register_avail and event.register_avail != 9999" t-attf-class="label pull-right label-#{ event.register_avail &lt;= 10 and 'warning' or 'info' }">
                                             <t t-if="event.register_avail &lt;= 10">Only</t>
                                             <t t-esc="event.register_avail"/>
                                             <t t-if="event.register_avail &gt; 1">tickets</t>
@@ -57,7 +57,7 @@
                                             available.
                                         </span>
                                     </t>
-                                    <h4 class="media-heading"><a t-att-href="'/event/%%s/' %% event.id"><span t-field="event.name"> </span></a></h4>
+                                    <h4 class="media-heading"><a t-attf-href="/event/#{ event.id }/"><span t-field="event.name"> </span></a></h4>
                                     <t t-call="website.publish"><t t-set="object" t-value="event"/></t>
                                     <div>
                                         <span t-field="event.type">: </span>
@@ -89,7 +89,7 @@
                 <li class="nav-header">Category</li>
                 <t t-foreach="types">
                     <li t-if="type" t-att-class="searches.get('type') == str(type and type[0]) and 'active' or ''">
-                        <a t-att-href="'/event/%%s&amp;type=%%s' %% (search_path, type[0])"><t t-esc="type[1]"/> <small>(<t t-esc="type_count"/>)</small></a>
+                        <a t-attf-href="/event/#{ search_path }&amp;type=#{ type[0] }"><t t-esc="type[1]"/> <small>(<t t-esc="type_count"/>)</small></a>
                     </li>
                 </t>
             </ul>
@@ -101,7 +101,7 @@
                 <li class="nav-header">Location</li>
                 <t t-foreach="countries">
                     <li t-if="country_id" t-att-class="searches.get('country') == str(country_id and country_id[0]) and 'active' or ''">
-                        <a t-att-href="'/event/%%s&amp;country=%%s' %% (search_path, country_id[0])"><t t-esc="country_id[1]"/><small>(<t t-esc="country_id_count"/>)</small></a>
+                        <a t-attf-href="/event/#{ search_path }&amp;country=#{ country_id[0] }"><t t-esc="country_id[1]"/><small>(<t t-esc="country_id_count"/>)</small></a>
                     </li>
                 </t>
             </ul>
@@ -138,7 +138,7 @@
                             <t t-if="event_id.event_ticket_ids">
                                 <span t-if="event_id.register_avail == 9999" class="label pull-right">Tickets availables.</span>
                                 <span t-if="not event_id.register_avail" class="label pull-right">No ticket available.</span>
-                                <span t-if="event_id.register_avail and event_id.register_avail != 9999" t-att-class="'label pull-right label-%%s' %% (event_id.register_avail &lt;= 10 and 'warning' or 'info')">
+                                <span t-if="event_id.register_avail and event_id.register_avail != 9999" t-attf-class="label pull-right label-#{ event_id.register_avail &lt;= 10 and 'warning' or 'info' }">
                                     <t t-if="event_id.register_avail &lt;= 10">Only</t>
                                     <t t-esc="event_id.register_avail"/>
                                     <t t-if="event_id.register_avail &gt; 1">tickets </t>
@@ -146,7 +146,7 @@
                                     available.
                                 </span>
                             </t>
-                            <h4 class="media-heading"><a t-att-href="'/event/%%s/' %% event_id.id"><span t-field="event_id.name"> </span></a></h4>
+                            <h4 class="media-heading"><a t-attf-href="/event/#{ event_id.id }/"><span t-field="event_id.name"> </span></a></h4>
                             <t t-call="website.publish"><t t-set="object" t-value="event_id"/></t>
                             <h5 class="media-heading">
                                 <span t-field="event_id.address_id"/><br/>
@@ -154,7 +154,7 @@
                                 <i class="icon-time"></i> <span t-field="event_id.date_end"/>
                             </h5>
                             <h4 t-if="event_id.event_ticket_ids">Ticket Information</h4>
-                            <form t-att-action="'/event/%%s/add_cart' %% event_id.id" method="post" t-if="event_id.event_ticket_ids">
+                            <form t-attf-action="/event/#{ event_id.id }/add_cart" method="post" t-if="event_id.event_ticket_ids">
                                 <table class="table">
                                     <thead>
                                         <tr>
@@ -172,7 +172,7 @@
                                             <td t-field="ticket.price"/>
                                             <td><span t-if="ticket.register_max"><t t-esc="ticket.register_current"/>/<t t-field="ticket.register_max"/></span></td>
                                             <td>
-                                                <select t-if="ticket.register_avail" t-att-name="'ticket-%%s' %% ticket.id">
+                                                <select t-if="ticket.register_avail" t-attf-name="ticket- #{ ticket.id }">
                                                     <t t-foreach="range(0, ticket.register_avail > 9 and 10 or ticket.register_avail+1 )" t-as="nb"><option t-esc="nb"/></t>
                                                 </select>
                                                 <span t-if="not ticket.register_avail">Not ticket available</span>
diff --git a/addons/website_mail/views/website_mail.xml b/addons/website_mail/views/website_mail.xml
index 236da4b3817..b96c58fff6d 100644
--- a/addons/website_mail/views/website_mail.xml
+++ b/addons/website_mail/views/website_mail.xml
@@ -34,7 +34,7 @@
             <div class="container mt48 js_website_mail">
                 <div class="row">
                     <div class="span4" id="left_column">
-                        <a t-if="mail_group_id and editable" t-att-href="'/blog/%%s/new' %% mail_group_id" class="btn">Add a new Blog</a>
+                        <a t-if="mail_group_id and editable" t-attf-href="/blog/#{ mail_group_id }/new" class="btn">Add a new Blog</a>
 
                         <div id="blog_subscribe">
                             <form action="./subscribe" method="POST" class="form-inline" t-if="not subscribe">
@@ -69,7 +69,7 @@
                                         </small>
                                     </div>
                                 </li>
-                                <form id="post" t-att-action="'/blog/%%s/%%s/post#post' %% (blog_id.res_id, blog_id.id)" method="POST" class="form-horizontal text-center" groups="group_website_mail_reply">
+                                <form id="post" t-attf-action="/blog/#{ blog_id.res_id }/#{ blog_id.id }/post#post" method="POST" class="form-horizontal text-center" groups="group_website_mail_reply">
                                     <textarea rows="4" placeholder="Your comment" class="span7"> </textarea>
                                     <button type="submit" class="btn">Post your comment</button>
                                 </form>
@@ -80,14 +80,14 @@
                     <div class="span8" t-if="not blog_id and blog_ids">
                         <ul class="media-list">
                             <li t-foreach="blog_ids" t-as="blog" class="media well">
-                                <div t-att-class="'media-body %%s' %% (blog.website_published and 'css_published' or '')">
+                                <div t-attf-class="media-body #{ 'css_published' if blog.website_published else '' }">
                                     <t t-call="website.publish"><t t-set="object" t-value="blog"/></t>
-                                    <h4 class="media-heading" ><a t-att-href="'/blog/%%s/%%s#comment' %% (blog.res_id, blog.id)" t-field="blog.subject"></a></h4>
+                                    <h4 class="media-heading" ><a t-attf-href="/blog/#{ blog.res_id }/#{ blog.id }#comment" t-field="blog.subject"></a></h4>
                                     <div class="media">
                                         <div t-field="blog.body"/>
                                         <small class="pull-left muted text-right" t-if="len(blog.child_ids)">
-                                            <a t-if="len(blog.child_ids) &lt;= 1" t-att-href="'/blog/%%s/%%s#comment' %% (blog.res_id, blog.id)"><t t-esc="len(blog.child_ids)"/> Comment</a>
-                                            <a t-if="len(blog.child_ids) > 1" t-att-href="'/blog/%%s/%%s#comment' %% (blog.res_id, blog.id)"><t t-esc="len(blog.child_ids)"/> Comments</a>
+                                            <a t-if="len(blog.child_ids) &lt;= 1" t-attf-href="/blog/#{ blog.res_id }/#{ blog.id }#comment"><t t-esc="len(blog.child_ids)"/> Comment</a>
+                                            <a t-if="len(blog.child_ids) > 1" t-attf-href="/blog/#{ blog.res_id }/#{ blog.id }#comment"><t t-esc="len(blog.child_ids)"/> Comments</a>
                                         </small>
                                         <small class="pull-right muted text-right">
                                             <div t-field="blog.author_id"/>
@@ -109,7 +109,7 @@
     <template id="blog_history" inherit_id="website_mail.index" inherit_option_id="website_mail.index" name="History">
         <xpath expr="//div[@id='left_column']" position="inside">
             <ul class="nav nav-list">    
-                <li class="nav-header"><a t-att-href="'/blog/%%s/' %% mail_group_id">BLOG ARCHIVE</a></li>
+                <li class="nav-header"><a t-attf-href="/blog/#{ mail_group_id }/">BLOG ARCHIVE</a></li>
                 <!-- TODO: check qweb iteration -->
                 <li t-foreach="nav_list" t-as="year" class="js_nav_year">
                     <t t-set="year" t-value="nav_list[year]"/>
diff --git a/addons/website_sale/views/website_sale.xml b/addons/website_sale/views/website_sale.xml
index 77ae340fc30..3bcd38c76c4 100644
--- a/addons/website_sale/views/website_sale.xml
+++ b/addons/website_sale/views/website_sale.xml
@@ -356,7 +356,7 @@
                     </div>
                     <form class="span8 form-horizontal" action="/shop/confirm_order/" method="post">
                         <div class=" row">
-                            <a t-if="not partner" t-att-href="'/admin#action=redirect&amp;url=%%s/shop/checkout/' %% host_url" class="btn btn-primary">Log me, I have an account</a>
+                            <a t-if="not partner" t-attf-href="/admin#action=redirect&amp;url=#{ host_url }/shop/checkout/" class="btn btn-primary">Log me, I have an account</a>
                             <h3 class="span8">Billing Information</h3>
                              <div t-attf-class="control-group #{error.get('name', '')}">
                                 <label class="control-label" for="contact_name">Name and firstname</label>