diff --git a/addons/mail/static/src/core/web/chatter.scss b/addons/mail/static/src/core/web/chatter.scss
index f7d06b8250b..7743436514a 100644
--- a/addons/mail/static/src/core/web/chatter.scss
+++ b/addons/mail/static/src/core/web/chatter.scss
@@ -34,7 +34,7 @@
      * To by-pass SCSS min() shadowing CSS min(), we rely on SCSS being case-sensitive while CSS isn't.
      */
     max-width: Min(400px, 95vw);
-    max-height: Min(500px, 95vh);
+    max-height: Min(500px, 50vh);
 }
 
 .o-mail-Follower-avatar {