https://bugs.winehq.org/show_bug.cgi?id=57370
--- Comment #5 from Ivo Ivanov logos128@gmail.com --- I have now tried only apps with systray icons that function properly (with the latest master 3a736901cdd588ba7fbb4318e5f5069793268a01). They are all installed in the same prefix, so started them (TrackIR5, JoyToKey and SimHub) in the same session. As I launched them one by one, tried each systray icon and each responded correctly to mouse clicks, displayed a context menu, etc. Then closed one of the apps. The systray icons of the remaining apps stopped responding to mouse clicks, despite the fact that they all work properly in individual sessions.
This always happens regardless of which app is closed first, or the number of apps started. They just have to be more than one. Apparently this isn't caused by Steam either, as it happens with any app. IMO there is something with the focus of the systray windows. Winex11.drv doesn't seem to take into account that there are still active systray windows, after closing one of them.
I looked in the steam-systray-bug.log, and it seems that Steam also opens two systray windows, so the issue with Steam might be related.