https://www.mordorintelligence.com/v7.0.0/express-js/flash-add-source.js

1// const attachCopyListener = () => {
2//     document.addEventListener("copy", (event) => {
3//       handleCopyEvent(event);
4//     });
5//   };
6 
7//   const handleCopyEvent = (event) => {
8//     const selectedRange = window.getSelection().getRangeAt(0);
9//     const clonedContents = selectedRange.cloneContents();
10//     const sourceLink = `Source: ${document.location.href}`;
11//     const temporaryDiv = document.createElement("div");
12 
13//     temporaryDiv.appendChild(clonedContents);
14 
15//     const plainTextData = `${temporaryDiv.innerText} ${sourceLink}`;
16//     const htmlData = `${temporaryDiv.innerHTML}<br>${sourceLink}<br>`;
17 
18//     event.clipboardData.setData("text/plain", plainTextData);
19//     event.clipboardData.setData("text/html", htmlData);
20//     event.preventDefault();
21//   };
22 
23//   attachCopyListener();
24
25const attachCopyListener = () => {
26  document.addEventListener("copy", handleCopyEvent);
27};
28
29const handleCopyEvent = (event) => {
30  const selection = window.getSelection();
31  if (!selection || selection.isCollapsed) return;
32
33  // Let browser prepare the default copied content first
34  const selectedText = selection.toString();
35  if (!selectedText) return;
36
37  const sourceText = `\n\nSource: ${document.location.href}`;
38
39  // Read what browser already copied (plain text)
40  const clipboard = event.clipboardData;
41  const defaultText = selectedText;
42
43  // Only append source, keep everything else untouched
44  clipboard.setData("text/plain", defaultText + sourceText);
45
46  // ❗ Do NOT touch text/html → browser keeps default HTML copy
47  event.preventDefault();
48};
49
50attachCopyListener();