diff --git a/addons/web/static/src/core/dialog/dialog.scss b/addons/web/static/src/core/dialog/dialog.scss
index 18782781c07..429a11c6155 100644
--- a/addons/web/static/src/core/dialog/dialog.scss
+++ b/addons/web/static/src/core/dialog/dialog.scss
@@ -1,52 +1,7 @@
-.o_dialog {
-  > .modal {
-    display: block;
-  }
-}
-
-.modal.o_technical_modal {
-  .modal-content {
-    border-radius: 0;
-
-    .modal-header .modal-title {
-      word-break: break-word;
-    }
-
-    .modal-footer {
-      flex-wrap: wrap;
-      text-align: left;
-      justify-content: flex-start;
-
-      footer {
-        > :not(:first-child) {
-          margin-left: 0.25rem;
-        }
-        > :not(:last-child) {
-          margin-right: 0.25rem;
-        }
-        button {
-          margin-bottom: 0.5rem;
-        }
-      }
-    }
-  }
-
-  @include media-breakpoint-up(sm) {
-    .modal-dialog .modal-content.o_dialog_error .modal-body {
-      overflow: visible;
-      display: flex;
-      flex-flow: column nowrap;
-
-      > .alert,
-      > button {
-        flex: 0 0 auto;
-      }
-
-      > .o_error_detail {
-        flex: 1 1 auto;
-        min-height: 0;
-        overflow: auto;
-      }
-    }
-  }
+.modal.o_technical_modal .modal-footer {
+    gap: map-get($spacers, 1);
+
+    button {
+        margin: 0; // Reset boostrap.
+    }
 }
diff --git a/addons/web/static/src/core/dialog/dialog.xml b/addons/web/static/src/core/dialog/dialog.xml
index 82a58ca57ec..8d38e572e64 100644
--- a/addons/web/static/src/core/dialog/dialog.xml
+++ b/addons/web/static/src/core/dialog/dialog.xml
@@ -3,7 +3,7 @@
 
     <t t-name="web.Dialog" owl="1">
         <div class="o_dialog" t-att-class="{ o_inactive_modal: !props.isActive }" t-on-dialog-closed="close">
-            <div role="dialog" class="modal"
+            <div role="dialog" class="modal d-block"
                 tabindex="-1"
                 t-att-class="{ o_technical_modal: technical, o_modal_full: fullscreen }"
                 t-ref="modal"
@@ -11,7 +11,7 @@
                 <div class="modal-dialog" t-att-class="size">
                     <div class="modal-content" t-att-class="contentClass">
                         <header t-if="renderHeader" class="modal-header">
-                            <h4 class="modal-title">
+                            <h4 class="modal-title text-break">
                                 <t t-esc="title"/>
                             </h4>
                             <button type="button" class="close" aria-label="Close" tabindex="-1" t-on-click="close">×</button>
@@ -19,7 +19,7 @@
                         <main class="modal-body">
                             <t t-call="{{ constructor.bodyTemplate }}"/>
                         </main>
-                        <footer t-if="renderFooter" class="modal-footer">
+                        <footer t-if="renderFooter" class="modal-footer justify-content-start">
                             <t t-call="{{ constructor.footerTemplate }}" />
                         </footer>
                     </div>
diff --git a/addons/web/static/src/legacy/scss/modal.scss b/addons/web/static/src/legacy/scss/modal.scss
index d5faa77177d..9ec710d58fc 100644
--- a/addons/web/static/src/legacy/scss/modal.scss
+++ b/addons/web/static/src/legacy/scss/modal.scss
@@ -1,7 +1,5 @@
 .modal.o_technical_modal {
-
     .modal-content {
-        border-radius: 0;
 
         .modal-header .o_subtitle {
             margin-left: 10px;
@@ -54,14 +52,6 @@
             > div, > footer {
                 flex: 1 1 auto;
             }
-
-            footer {
-                > :not(:first-child) { margin-left: .25rem; }
-                > :not(:last-child) { margin-right: .25rem; }
-                button {
-                    margin-bottom: .5rem;
-                }
-            }
         }
     }
 
diff --git a/addons/web/static/src/webclient/actions/action_dialog.xml b/addons/web/static/src/webclient/actions/action_dialog.xml
index 9238bd9687d..9af80efc355 100644
--- a/addons/web/static/src/webclient/actions/action_dialog.xml
+++ b/addons/web/static/src/webclient/actions/action_dialog.xml
@@ -5,7 +5,7 @@
     <xpath expr="//header/h4[contains(concat(' ',normalize-space(@class),' '),' modal-title ')]" position="before">
       <DebugMenu t-if="env.debug" />
     </xpath>
-    <xpath expr="//main[@class='modal-body']" position="attributes">
+    <xpath expr="//main[hasclass('modal-body')]" position="attributes">
       <attribute name="t-att-class">
         {"o_act_window": actionType === "ir.actions.act_window"}
       </attribute>