@luminance88 I think they fixed them to work in the first workspace. Mute button in other workspaces will work as you would click in the first workspace so if you click speaker icon on 1st tab in 3rd workspace then 1st tab in 1st workspace will be muted/unmuted instead.
Stable version 99.x has been released and published. It removes all reported problems from version 98.x (including lack of subtitles in speed dial directories and inactive right-click menu in the Google search bar). Way To Go! 👌🏼 👍🏼
I often had this with Vivaldi browser. It seems to be a problem with resolving of DNS.
But troubleshooting could be to shut down your internet router and start it again after a one minute wait.