Comment 3 for bug 692635

Just came up with the following theory:

gui/main/info_bar.py connects to the general hub in order to be notified changes to the download speed and to update the corresponding label in the GUI. It seems like this handler is run in the same thread as the one that updated the download speed value in the general hub, which is not necessarily the main thread. It might be possible that updating the GUI state from another thread results in rare race conditions throughout the execution of the application. Thus, forcing the handler to run in the main thread might solve the problem.

I'll make this change and look for other such occurrences. After that, we'll see whether we still experience these mysterious crashes.