Priority: P3: Somewhat important
Affects Version/s: 5.15.2
Fix Version/s: None
Component/s: GUI: Basic Input System (keyboard, mouse, touch)
Environment:Linux Mint 20.1 using Cinnamon 4.8.6
Qt Creator 4.14.0 for building Qt Applications
Tray Icons created using QSytemTrayIcon do not receive mouse based QEvents (clicking, scroll wheel, etc.) in the Cinnamon DE.
Right clicking on the icon brings up the context menu, but does not generate a "QSystemTrayIcon::activated" signal with the "QSystemTrayIcon::Context" reason.
Left and middle clicking generate a "QSystemTrayIcon::activated" signal with appropriate "QSystemTrayIcon::ActivationReason", but don't generate "QEvent::MouseButtonPress" or "QEvent::MouseButtonRelease".
Scrolling the mouse wheel does not trigger a "QSystemTrayIcon::event". As far as I know that's the only way to receive QWheelEvents, so without it my application cannot interact with the scroll wheel.
Scroll wheel events worked as expected under a previous version of Cinnamon (can't check the version, that machine is not working) running on top of Ubuntu 16.04 LTS, but then stopped working when that same code was run on Linux Mint 20.1 using Cinnamon 4.8.6.
Mouse wheel scrolling works fine with tray icons generated by other applications.
Attached are the test code and .pro files that I used to verify the problem.