I was reading 'Mysterious Supervisor and saw this
Given your description, I might guess its a hook. To see current hooks:
So I have a question about Hooks, given that
reveals the following…
As I don’t use Thunderbird, and installed from the Minimal KDE install Why would those hooks be there.
… and I may be answering my own question. Unless I removed Thunderbied after Installation
But I’ve added and removed many other apps, and their Hooks don’t seem to appear there.