Headless host exits with "thread blocked indefinitely in an MVar operation"

[ryantrinkle]

I think this happens when everything that could possibly trigger an event is dead. Instead, the app should remain running indefinitely.

[maralorn]

I got the same Errormessage when I tried to finish an app with "exitFailure": It prints the failure exception, then the MVar error and then exits.

Please don‘t remain running indefinitely in that case. But I think it shouldn‘t show this error and instead exit cleanly when an exception is raised.