so update on the status of this, apparently there is a bug in the QSystemTrayIcon Class, you can see it here: https://bugreports.qt.io/browse/QTBUG-31762
So maybe there's a way for ubuntu users to use QT 4.8.4 without screwing up the rest of the code for everyone else? Maybe?
Or do we just wait it out until there's an updated version of QT without the bug?
As others in that thread have said, the problem still exists on Ubuntu 14.04 with Qt 5.3 and Qt 5.4. And I can confirm that the problem exists for the BitShares Qt client specifically for builds linked against Qt 5.3 and Qt 5.4.
I kinda doubt Qt 4.8.4 would be acceptable for BitShares. I had to upgrade from Qt 5.3 to Qt 5.4 to just get the light wallet working.
It seems like those Qt devs aren't in any kind of rush to fix it anytime soon, considering this bug has existed for over a year...
Maybe as a workaround we could have a cmake flag that disables the system tray icon entirely? Closing the window would actually shut down the program and Ubuntu users would have to only minimize the program if they want it out of sight but still running.