Merge branch 'viewport-switcher' of github.com:magento/magento2-page-builder into 636-add-tooltip-with-viewport-label-description

Author: omiroshnichenko

app/code/Magento/PageBuilder/view/adminhtml/web/css/source/_buttons.less

@@ -59,6 +59,13 @@
         opacity: 1;
     }
 
+    &:not([disabled]) {
+        &:hover {
+            background-color: #4a4542;
+            opacity: 1;
+        }
+    }
+
     img {
         height: 20px;
         width: 30px;