Re-added a piece of code and commented it for future generations

src/css/sidebar.scss

@@ -25,6 +25,10 @@
       color: #fff;
       background: #f27506;
       border-radius: 3px;
+      // This is here on purpose. Sometimes text-indent is applied on the parent
+      // element and gets inherited by the PRO label, which it is not supposed
+      // to do:
+      text-indent: 0;
     }
   }