These latest Windows 11 builds (the Moment 2 update and later) have broken the ability to middle click tray app icons.
On all previous versions on Windows (at least since W10), middle clicking was allowed and some apps make use of it for extra functionality.
Now, ever since these updates, middle clicking the tray icon will trigger a "left click" event instead of a "middle click" event.
This has been verified with multiple test apps using Winforms, WPF and WinUI. The issue happens regardless of tech and is almost for sure related with these last Windows updates that introduced new changes to the tray area.
This has been tested and verified on multiple systems and VMs. I have reported this issue to @WindowsUpdate on Twitter and was recommended to report it through the "Feedback Hub" app. I have reported it there, but have gotten absolutely no response or feedback from anybody, so my report is sitting there with a single upvote so I'm sure it will most likely be ignored.
Reporting it here as well to try and get some eyes on this by any relevant person/dev.