The only app I've found that works is Remmina, but of course that only runs on Linux. Apparently the issue is with encryption, which I don't even need because all traffic is staying on my LAN (behind my pfSense firewall). So, although it's not idea, I could just disable VNC encryption, but I haven't found a way to do so as of yet.
For Win/Mac VNC clients so far I've tried:
- uVNC client
- RealVNC Viewer (aka VNC Connect)
- Default "Screen Sharing.app" on macOS
None of them work. What app on Mac and/or Windows meets the encryption standards that Fedora and/or Ubuntu are using for the baked in "Screen Sharing"?
