diff --git a/app/javascript/styles/cybre-base.scss b/app/javascript/styles/cybre-base.scss
index 1dd643e3f..0c9e23a59 100644
--- a/app/javascript/styles/cybre-base.scss
+++ b/app/javascript/styles/cybre-base.scss
@@ -1,4 +1,3 @@
-
 @import 'application';
 
 /* Wider compose area */
@@ -82,5 +81,10 @@
   }
 }
 
-@import 'fullwidth-media';
+/* Don't display the weird triangles on the modal layout,
+ * because they look strange on cybrespace themes. */
+.modal-layout__mastodon {
+  display:none;
+}
 
+@import 'fullwidth-media';