diff --git a/theme/base/style/core.css b/theme/base/style/core.css
index 6f02ac71f46..90071011071 100644
--- a/theme/base/style/core.css
+++ b/theme/base/style/core.css
@@ -1511,7 +1511,6 @@ img#persona_signin { cursor: pointer; }
 .moodle-actionmenu[data-enhanced].show .menu a.hidden {display: none;}
 .moodle-actionmenu[data-enhanced].show .menu img {vertical-align: middle;}
 .moodle-actionmenu[data-enhanced].show .menu > li {display: block;}
-.action-menu-shown .moodle-actionmenu[data-enhanced] .toggle-display {background-color: #FFF;}
 .block .moodle-actionmenu {text-align: right;}
 
 .dir-rtl .block .moodle-actionmenu {text-align: right;}
diff --git a/theme/bootstrapbase/less/moodle/core.less b/theme/bootstrapbase/less/moodle/core.less
index e7e9247f380..c88f643e8df 100644
--- a/theme/bootstrapbase/less/moodle/core.less
+++ b/theme/bootstrapbase/less/moodle/core.less
@@ -2119,10 +2119,6 @@ img#persona_signin {
     }
 }
 
-.action-menu-shown .moodle-actionmenu[data-enhanced] .toggle-display {
-    background-color: #FFF;
-}
-
 .block .moodle-actionmenu {
     text-align: right;
 }