Is this the one-time signature checking that has been in place since Catalina, or is this something else? (And if so is there any information about it?)
Presumably something changed, but so far I haven't heard an explanation that makes sense of it.
Anecdotally, I'm using Mojave and experienced this issue, a person I was trying to have a Zoom call with was experiencing the same issue on their Mojave.
I think there are enough comments scattered across Hacker News to safely conclude that it affected Mojave too - although it's possible the timeout behaviour / error handling is different to Catalina.
[1] https://gs.statcounter.com/macos-version-market-share/deskto...