Cleanup element classes and attributes on unbound

Author: piroor

webextensions/common/Tab.js

@@ -207,6 +207,14 @@ export default class Tab {
 
   unbindElement() {
     if (this.element) {
+      for (const state of this.states) {
+        this.element.classList.remove(state);
+        if (state == Constants.kTAB_STATE_HIGHLIGHTED)
+          this.element.removeAttribute('aria-selected');
+      }
+      for (const key of Object.keys(this.attributes)) {
+        this.element.removeAttribute(name);
+      }
       this.element.$TST = null;
       this.element.apiTab = null;
     }