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Closes #4912

Merge request studip/studip!3687

resources/assets/stylesheets/scss/header.scss

@@ -208,6 +208,7 @@
 
             .action-menu-icon {
                 border: 1px solid var(--dark-gray-color-40);
+                border-left: none;
                 background-color: var(--dark-gray-color-5);
                 height: 28px;
                 margin: 0 22px 0 0;