I am on a Roku Ultra with Roku beta 3.0.158 and I upgraded my secondary server to beta 188.8.131.52
When I attempt to switch from my primary server (running the release ver 184.108.40.206) to the beta one and I select a user instead of offering a password screen I am kicked out to the main Roku screen.
I can use the standard Roku app (3.0.155) and then I can log onto the beta server just fine and after logging on via the standard app the Roku beta app accesses the beta server just fine and I can log off it and onto the standard server without issue.
However if I then try to access the beta server again I crash back to Roku's home screen.
I have restarted my Roku and the problem persists.