Linux: icon glitch in statusbar on autostart

[ghost]

Icon is sometimes glitchy in the status bar. I can't tell exactly, when it is and when it's not, just in most cases it is. The client starts automatically every boot. I'm XFCE user (gtk2). Using version 2.8.0 from AUR. If I restart client manually, the icon is fixed. Seems to be an issue with some kind of "lazy positioning", when another icon on status bar loads and moves the client a bit, repositioning but not freeing the frame (however this could be totally false). How can I help you to resolve this?

[ghost]

I've spotted that this happens only if any other app is started (and if it has an icon in status bar). In my example, when I manually start goldendict after mega, the glitch happens, but when mega starts as a last one, it doesn't.

[ghost]

Closing because most probably that was a Qt 5.5-5.6 bug.