I am unable to add a workspace. It tells me the workspace isn't a valid URL. It works on older versions of Remote Desktop.
I had the same issue. I tried to find a version of RDS Beta that works. I have tried a lot of versions and it seems like the latest version that works for me is 2022 August - (Version 10.7.9). The next version (10.8.0) and following don't work anymore and gives the error that workspace URL is not valid. I don't think it is a coincidence. Just providing here as an input in case Microsoft decides to investigate the issue. Thanks!