diff --git a/src/js/popup.js b/src/js/popup.js
index 890b959..19166a1 100644
--- a/src/js/popup.js
+++ b/src/js/popup.js
@@ -1189,7 +1189,7 @@ Logic.registerPanel(P_CONTAINER_ASSIGNMENTS, {
           delete assignments[siteKey];
           this.showAssignedContainers(assignments);
         });
-        trElement.classList.add("menu-item", "hover-highlight", " keyboard-nav");
+        trElement.classList.add("menu-item", "hover-highlight", "keyboard-nav");
         tableElement.appendChild(trElement);
       });
     }