Michael J Gruber <michaeljgruber+grubix+git@gmail.com> writes:

> It took more runs to get some fails now, and archs vary, so I still
> think its a time out. And no way to get it locally so far.

I can duplicate it locally about once every 40 runs of the complete test
suite.

> ENOLISP (for me) but could it be the case that notmuch-test-wait can
> abort its while loop too early if the first buffer write takes longer
> than the timeout, or if some other process writes (because the process
> parameter is nil)? Is something different for emacs 29 in this regard?
> Any clues from sbuild?

Can you try the attached patch? It needs more testing, but I did get 140
runs of the test suite without an error.