A browser keeps kestrove-nmh.exe running while the extension is connected, so an update couldn't replace it and stopped half way: the old version's uninstall had already removed the browser registration, and the new one was never written. The installer only closes the app itself, so the hooks now stop the helper too. It holds no state; the browser starts it again. Co-Authored-By: Claude Opus 5.5 <[email protected]>