preventDefault on paste event does not prevent default paste behavior

Phenomenon

In Chrome on Windows, calling preventDefault() on the paste event does not always prevent the default paste behavior. Content may still be pasted despite the prevention.

Reproduction example

1. Create a contenteditable div.
2. Add a paste event listener that calls event.preventDefault().
3. Copy some text.
4. Paste into the contenteditable.
5. Observe whether the paste is prevented.

Observed behavior

• In Chrome on Windows, preventDefault() on paste may not work.
• Content may still be pasted.
• The default behavior is not consistently prevented.

Expected behavior

• preventDefault() on paste should prevent the default paste behavior.
• No content should be pasted when prevented.
• The behavior should be consistent and reliable.