If I use zsh, I'm good. If I enter BASH from zsh, I get kicked out after several seconds. Definitely is something to do with BASH.
Stupid tryout: use bash and then enter zsh before being kicked out. Still out?
To understand if it is the firing of bash itself or the stay in bash...
No, the underlying bash remains until the ZSH closes. Same as if you were running top from it, for example.
So basically bash is able to run long running jobs with your user...
It's the interactivity with the shell to be broken... Meh.
Sorry the thread is long, did you mention any test from zsh with:
Bash <-- ok this kills the session
Bash -i any difference???
Bash -l ???
From bashman page