2017 iMac with two external monitors, running 12.6, RDP client v10.2.9(2011), connected to Windows 11 Pro HyperV VM RDP desktop server.
Extending the Windows desktop to fill all three monitors results in a persistent problem with mouse focus. When the focus is in monitor "X", the first click in one of the other monitors has no effect. The second and subsequent clicks in the unfocused monitor work. So, quite annoying.
Everything works fine when connected to Windows 10 RDP server.
Just trying to help. Further details available on request, have a nice day. Btw, the UX on this “community” portal is about as crass as it gets. It just screams “don’t bother us by trying to find or post anything here”. Like a desperate, gratuitous attempt at tire-fire management. Again, just trying to help, details available on request.