Require sticky user activation or clipboard-read permission to fire `clipboardchange` events, preventing unauthorized clipboard monitoring. This is as per the spec defined here - https://www.w3.org/TR/clipboard-apis/#clipboard-event-clipboardchange Reason for PSA - Clipboardchange event is relatively new (144) and this has minimal web facing change. It is expected that in most cases sticky activation / clipboard-read permission would already be present where clipboard monitoring is done (like remote desktop clients)
The `clipboardchange` event allows web pages to be notified when the system clipboard contents change. Without security controls, malicious sites could passively monitor clipboard changes without any user interaction, enabling privacy violations such as tracking sensitive data (passwords, personal information) or detecting when users copy content from other applications. This feature adds security requirements to prevent unauthorized clipboard monitoring: events will only fire when the page has sticky user activation (recent click/tap/keypress) OR has been granted explicit clipboard-read permission. This prevents passive surveillance while preserving legitimate use cases like collaborative editors (which have user interaction) and clipboard manager tools (which request permission).