show shared link enable button on disabled link page

app/javascript/elements/check_on_click.js

@@ -1,7 +1,7 @@
 export default class extends HTMLElement {
   connectedCallback () {
     this.addEventListener('click', () => {
-      if (!this.element.checked) {
+      if (this.element && !this.element.disabled && !this.element.checked) {
         this.element.checked = true
         this.element.dispatchEvent(new Event('change', { bubbles: true }))
       }