diff --git a/addons/website/data/ir_asset.xml b/addons/website/data/ir_asset.xml
index 7ae97f1475d..b741ccd89b8 100644
--- a/addons/website/data/ir_asset.xml
+++ b/addons/website/data/ir_asset.xml
@@ -17,13 +17,6 @@
             <field name="sequence" eval="99"/>
         </record>
 
-        <record id="website.bs3_for_12_0_scss" model="ir.asset">
-            <field name="name">Bs3 for 12 0 SCSS</field>
-            <field name="bundle">web.assets_frontend</field>
-            <field name="path">website/static/src/scss/compatibility/bs3_for_12_0.scss</field>
-            <field name="active" eval="False"/>
-        </record>
-
         <record id="website.configurator_tour" model="ir.asset">
             <field name="key">website.configurator_tour</field>
             <field name="name">Website Configurator Tour</field>
diff --git a/addons/website/static/src/scss/compatibility/bs3_for_12_0.scss b/addons/website/static/src/scss/compatibility/bs3_for_12_0.scss
deleted file mode 100644
index 3078313656a..00000000000
--- a/addons/website/static/src/scss/compatibility/bs3_for_12_0.scss
+++ /dev/null
@@ -1,355 +0,0 @@
-/**
- * This file's purpose is to *ease* migration from 11.0.
- */
-
-// Restore gray utilities
-$-compat-gray-map: (
-    'gray-darker': '900',
-    'gray-dark': '900',
-    'gray': '700',
-    'gray-light': '600',
-    'gray-lighter': '200',
-) !default;
-@each $old, $new in $-compat-gray-map {
-    @if not map-has-key($grays, $old) {
-        @include bg-variant(".bg-#{$old}", map-get($grays, $new));
-        @include text-emphasis-variant(".text-#{$old}", map-get($grays, $new));
-    }
-}
-
-// Restore media ?
-
-// Restore progress bars
-@each $color, $value in $theme-colors {
-    @include bg-variant(".progress-bar-#{$color}", $value);
-}
-
-// Adapt radio ?
-
-// Adapt labels
-.label {
-    @extend .badge;
-}
-@each $color, $value in $theme-colors {
-    .label-#{$color} {
-        @include badge-variant($value);
-    }
-}
-.label-default {
-    @include badge-variant(map-get($theme-colors, 'secondary'));
-}
-
-// Adapt center-block
-.center-block {
-    display: block;
-    margin: auto;
-}
-
-// Adapt pull-* classes
-.pull-left {
-    float: left;
-}
-.pull-right {
-    float: right;
-}
-
-// Adapt pagination
-.pagination > li {
-    @extend .page-item;
-    > a {
-        @extend .page-link;
-    }
-}
-
-// Adapt carousel
-.carousel .item {
-    @extend .carousel-item;
-}
-
-// Adapt checkboxes ?
-
-// Adapt tables
-.table-condensed {
-    @extend .table-sm;
-}
-
-// Adapt forms
-.control-label {
-    @extend .col-form-label;
-}
-.help-block {
-    @extend .form-text;
-}
-.has-error .form-control {
-    @extend .is-invalid;
-}
-.has-success .form-control {
-    @extend .is-valid;
-}
-.form-horizontal .form-group {
-    @extend .row;
-}
-
-// Adapt list-inline
-.list-inline > li {
-    @extend .list-inline-item;
-}
-
-// Adapt list-group
-.panel .list-group {
-    @extend .list-group-flush;
-}
-
-// Adapt image utilies
-.img-rounded {
-    @extend .rounded;
-}
-.img-circle {
-    @extend .rounded-circle;
-}
-
-// Adapt input group
-.input-group {
-    .input-group-btn:first-child {
-        @extend .input-group-prepend;
-    }
-    .form-control ~ .input-group-btn {
-        @extend .input-group-append;
-    }
-    .input-group-addon {
-        @extend .input-group-append;
-        @extend .input-group-text;
-    }
-}
-
-// Adapt panels
-.panel {
-    @extend .card;
-}
-@each $color, $value in $theme-colors {
-    @include bg-variant(".panel-#{$color}", $value);
-}
-@include bg-variant(".panel-default", $white);
-.panel-heading {
-    @extend .card-header;
-}
-.panel-body {
-    @extend .card-body;
-}
-.panel-footer {
-    @extend .card-footer;
-}
-.well {
-    @extend .card;
-    @extend .card-body;
-}
-
-// Adapt grid (push-pull ?)
-$-compat-breakpoints: (
-  xs: map-get($grid-breakpoints, 'xs'),
-  sm: map-get($grid-breakpoints, 'md'),
-  md: map-get($grid-breakpoints, 'lg'),
-  lg: map-get($grid-breakpoints, 'xl'),
-);
-@each $breakpoint in map-keys($-compat-breakpoints) {
-    $infix: breakpoint-infix($breakpoint, $-compat-breakpoints);
-    $infix: if($infix != "", $infix, "-xs");
-
-    @include media-breakpoint-up($breakpoint, $-compat-breakpoints) {
-        // `$grid-columns - 1` because offsetting by the width of an entire row isn't possible
-        @for $i from 0 through ($grid-columns - 1) {
-            .col#{$infix}-offset-#{$i} {
-                @include make-col-offset($i, $grid-columns);
-            }
-        }
-    }
-}
-
-// Adapt breadcrumb
-.breadcrumb > li {
-    @extend .breadcrumb-item;
-}
-
-// Adapt nav
-.nav > li {
-    @extend .nav-item;
-    > a {
-        @extend .nav-link;
-    }
-}
-.nav-stacked {
-    flex-direction: column;
-}
-@include bg-variant(".navbar-default", $light);
-
-// Adapt img-responsive
-.img-responsive {
-    @extend .img-fluid;
-}
-
-// Adapt dropdowns
-.dropdown-menu {
-    a {
-        @extend .dropdown-item;
-    }
-    .divider {
-        @extend .dropdown-divider;
-    }
-}
-.dropdown-toggle .caret {
-    display: none;
-}
-
-// Adapt buttons
-.btn-default {
-    @include button-variant(map-get($theme-colors, 'secondary'), map-get($theme-colors, 'secondary'));
-}
-.btn-xs {
-    @extend .btn-sm;
-}
-
-// Adapt display classes
-.hide {
-    display: none !important;
-}
-// The 'show' class could be supported if defined here and like that,
-// unfortunately, BS4 still defines a 'show' class for other purposes which
-// conflict with this (tab-pane, fade effects, ...). Adding more complex rules
-// won't solve the problem as they would change css rules priorities.
-// .show {
-//     display: block !important;
-// }
-.hidden {
-    display: none !important;
-}
-.visible {
-    &-xs, &-sm, &-md, &-lg {
-        &, &-block, &-inline, &-inline-block {
-            display: none !important;
-        }
-    }
-    &-xs {
-        &, &-block {
-            @include media-breakpoint-down(md) {
-                display: block !important;
-            }
-        }
-        &-inline {
-            @include media-breakpoint-down(md) {
-                display: inline !important;
-            }
-        }
-        &-inline-block {
-            @include media-breakpoint-down(md) {
-                display: inline-block !important;
-            }
-        }
-    }
-    &-sm {
-        &, &-block {
-            @include media-breakpoint-only(md) {
-                display: block !important;
-            }
-        }
-        &-inline {
-            @include media-breakpoint-only(md) {
-                display: inline !important;
-            }
-        }
-        &-inline-block {
-            @include media-breakpoint-only(md) {
-                display: inline-block !important;
-            }
-        }
-    }
-    &-md {
-        &, &-block {
-            @include media-breakpoint-only(lg) {
-                display: block !important;
-            }
-        }
-        &-inline {
-            @include media-breakpoint-only(lg) {
-                display: inline !important;
-            }
-        }
-        &-inline-block {
-            @include media-breakpoint-only(lg) {
-                display: inline-block !important;
-            }
-        }
-    }
-    &-lg {
-        &, &-block {
-            @include media-breakpoint-up(xl) {
-                display: block !important;
-            }
-        }
-        &-inline {
-            @include media-breakpoint-up(xl) {
-                display: inline !important;
-            }
-        }
-        &-inline-block {
-            @include media-breakpoint-up(xl) {
-                display: inline-block !important;
-            }
-        }
-    }
-}
-.hidden {
-    &-xs {
-        @include media-breakpoint-down(md) {
-            display: none !important;
-        }
-    }
-    &-sm {
-        @include media-breakpoint-only(md) {
-            display: none !important;
-        }
-    }
-    &-md {
-        @include media-breakpoint-only(lg) {
-            display: none !important;
-        }
-    }
-    &-lg {
-        @include media-breakpoint-up(xl) {
-            display: none !important;
-        }
-    }
-}
-.visible-print {
-    display: none !important;
-
-    @media print {
-        display: block !important;
-    }
-
-    &-block {
-        display: none !important;
-
-        @media print {
-            display: block !important;
-        }
-    }
-    &-inline {
-        display: none !important;
-
-        @media print {
-            display: inline !important;
-        }
-    }
-    &-inline-block {
-        display: none !important;
-
-        @media print {
-            display: inline-block !important;
-        }
-    }
-}
-.hidden-print {
-    @media print {
-        display: none !important;
-    }
-}