[Glitch] Replace `execCommand` for copying text with the modern `clipboard` API

Port fb6d7ed475 to glitch-soc

Signed-off-by: Claire <claire.github-309c@sitedethib.com>

app/javascript/flavours/glitch/entrypoints/public.tsx

@@ -327,31 +327,24 @@ Rails.delegate(document, '.input-copy button', 'click', ({ target }) => {
 
   if (!input) return;
 
-  const oldReadOnly = input.readOnly;
+  navigator.clipboard
-
+    .writeText(input.value)
-  input.readOnly = false;
+    .then(() => {
-  input.focus();
-  input.select();
-  input.setSelectionRange(0, input.value.length);
-
-  try {
-    if (document.execCommand('copy')) {
-      input.blur();
-
       const parent = target.parentElement;
 
-      if (!parent) return;
+      if (parent) {
         parent.classList.add('copied');
 
         setTimeout(() => {
           parent.classList.remove('copied');
         }, 700);
       }
-  } catch (err) {
-    console.error(err);
-  }
 
-  input.readOnly = oldReadOnly;
+      return true;
+    })
+    .catch((error: unknown) => {
+      console.error(error);
+    });
 });
 
 const toggleSidebar = () => {