Remove dead code and provide the return value for error detection.

clipboard.js

@@ -1,23 +1,16 @@
 export const clipboard = function(superClass) {
   return class extends superClass {
     copy(content) {
-      copyToClipboard(content);
+      return copyToClipboard(content);
     }
   };
 };
 
 export const copyToClipboard = async (content) => {
-  const txtEl = document.createElement('input');
-  txtEl.type = 'hidden';
-  document.body.appendChild(txtEl);
-  txtEl.value = content;
-  
   try {
     await navigator.clipboard.writeText(content);
     return true;
   } catch (err) {
     return false;
-  } finally {
-    document.body.removeChild(txtEl);
   }
 }