Revert copy-text change and apply alternative fix

Reverts PR #3331 and applies the alternative fix originally proposed
in PR #3329

packages/node_modules/@node-red/editor-client/src/js/ui/clipboard.js

@@ -946,23 +946,26 @@ RED.clipboard = (function() {
         if (truncated) {
             msg += "_truncated";
         }
-        navigator.clipboard.writeText(value).then(function () {
+        var clipboardHidden = $('<textarea type="text" id="red-ui-clipboard-hidden" tabIndex="-1">').appendTo(document.body);
-            if (element) {
+        clipboardHidden.val(value).focus().select();
-                var popover = RED.popover.create({
+        var result =  document.execCommand("copy");
-                    target: element,
+        if (result && element) {
-                    direction: 'left',
+            var popover = RED.popover.create({
-                    size: 'small',
+                target: element,
-                    content: RED._(msg)
+                direction: 'left',
-                });
+                size: 'small',
-                setTimeout(function() {
+                content: RED._(msg)
-                    popover.close();
+            });
-                },1000);
+            setTimeout(function() {
-                popover.open();
+                popover.close();
-            }
+            },1000);
-            if (currentFocus) {
+            popover.open();
-                $(currentFocus).focus();
+        }
-            }
+        clipboardHidden.remove();
-        }).catch(err => { console.error("Failed to copy:",err) });
+        if (currentFocus) {
+            $(currentFocus).focus();
+        }
+        return result;
     }
 
     function importNodes(nodesStr,addFlow) {

packages/node_modules/@node-red/editor-client/src/sass/editor.scss

@@ -356,6 +356,11 @@ button.red-ui-button-small
     background: $secondary-background;
 }
 
+#red-ui-clipboard-hidden {
+    position: absolute;
+    top: -3000px;
+}
+
 .form-row .red-ui-editor-node-label-form-row {
     margin: 5px 0 0 50px;
     label {