Upstream has been contacted: unknown
This is a bit different to other posts in this category in that AnyDesk is already on Flathub. It was originally uploaded by @nedrichards (presumably in response to internal demand at Endless). I have ended up sort-of maintaining it because flatpak-external-data-checker was generating PRs for it but nobody was available to merge them.
However, I don’t actually use it, and don’t have time or motivation to investigate issues like this one about leaking processes which use 100% CPU when you try to quit it.
Help wanted from someone who actually uses it. As mentioned, flatpak-external-data-checker takes care of mechanically opening PRs when new releases are made.