Hi Stephan, > > But the offscreen BBitmap shouldn't even have a running looper, no ? > > No, it is not running. In BeOS, you have to "lock" the bitmap too, before > you call functions of an attached view. Is this app attaching the > BStatusBar to a bitmap? > That's precisely what the app is doing as far as I can tell, I spent quite some time tracking that down because I initially thought the debugger call was being tripped by the looper of the actual program window. Unfortunately, source is not available so that's as much as I can tell from here. Related to this, would anyone object if I modified ::check_lock to include the Name() of the looper that's not locked in the debugger() string? That would have saved me quite some debugging time :) Regards, Rene