Merge pull request '[fix] Implement function for clipboard copying; Fix bug 79836' (#110) from fix/79836 into release/v9.3.0

Reviewed-on: https://git.onlyoffice.com/ONLYOFFICE/server/pulls/110

AdminPanel/client/src/components/ConfigViewer/ConfigViewer.js

@@ -1,6 +1,7 @@
 import {useMemo} from 'react';
 import {useSelector} from 'react-redux';
 import {selectConfig, selectConfigLoading, selectConfigError} from '../../store/slices/configSlice';
+import {copyToClipboard} from '../../utils/copyToClipboard';
 import Button from '../Button/Button';
 import styles from './ConfigViewer.module.scss';
 
@@ -13,10 +14,7 @@ const ConfigViewer = () => {
     return config ? JSON.stringify(config, null, 2) : '';
   }, [config]);
 
-  const copyToClipboard = async () => {
-    if (!jsonString) return;
-    await navigator.clipboard.writeText(jsonString);
-  };
+  const handleCopy = () => copyToClipboard(jsonString);
 
   if (isLoading) {
     return <div className={styles.loading}>Loading configuration...</div>;
@@ -36,7 +34,7 @@ const ConfigViewer = () => {
         <p className={styles.description}>
           Sensitive parameters (passwords, keys, secrets) are shown as <span className={styles.redactedBadge}>REDACTED</span>.
         </p>
-        <Button onClick={copyToClipboard}>Copy JSON</Button>
+        <Button onClick={handleCopy}>Copy JSON</Button>
       </div>
       <div className={styles.configContent}>
         <pre className={styles.jsonPre}>{jsonString}</pre>

AdminPanel/client/src/utils/copyToClipboard.js

@@ -0,0 +1,35 @@
+/**
+ * Copies the given text to the clipboard.
+ * Uses Clipboard API when available, falls back to DOM (execCommand).
+ * @param {string} text - Text to copy.
+ * @returns {Promise<void>}
+ */
+export const copyToClipboard = async text => {
+  if (!text) return;
+  const copyViaDOM = () => {
+    const textarea = document.createElement('textarea');
+    textarea.value = text;
+    textarea.style.position = 'fixed';
+    textarea.style.left = '-9999px';
+    textarea.setAttribute('readonly', '');
+    document.body.appendChild(textarea);
+    textarea.focus();
+    textarea.setSelectionRange(0, text.length);
+    let copied = false;
+    try {
+      copied = document.execCommand('copy');
+    } finally {
+      document.body.removeChild(textarea);
+    }
+    if (!copied) throw new Error('Copy failed');
+  };
+  if (navigator.clipboard?.writeText) {
+    try {
+      await navigator.clipboard.writeText(text);
+    } catch {
+      copyViaDOM();
+    }
+  } else {
+    copyViaDOM();
+  }
+};