Calling ApplicationBase::quit() from a thread that isn't the message thread?

The documentation indicates that this should be possible: "it just posts a quit message to the main queue".

But on OS/X, at least, this results in an assertion failure:  JUCE Assertion failure in juce_mac_MessageManager.mm:242

This was easily fixed by just posting a CallbackMessage that called ApplicationBase::quit(), but you might consider changing either the documentation or the code...

Good point - actually, it's only on OSX that there was a problem with threading, but I've sorted that out now, and it's possible to call it from other threads on all OSes.