diff --git a/addons/mail/static/src/core/web/chatter.xml b/addons/mail/static/src/core/web/chatter.xml
index c2d9d099de3..181ddc9fafd 100644
--- a/addons/mail/static/src/core/web/chatter.xml
+++ b/addons/mail/static/src/core/web/chatter.xml
@@ -87,7 +87,7 @@
                         </div>
                     </button>
                 </div>
-                <button t-if="props.close" class="o-mail-Chatter-close btn btn-dark flex-shrink-0 rounded-bottom-3" aria-label="Close" t-on-click="props.close">
+                <button t-if="props.close" class="o-mail-Chatter-close btn btn-secondary flex-shrink-0 ms-2" aria-label="Close" t-on-click="props.close">
                     <i class="oi oi-large oi-close"/>
                 </button>
             </div>