Simultaneously with the Timeout error message that has been reported in other topics before: Joining meeting timeout from Web SDK - #32 by ronen.landesman
we have found the Already has other meetings in a progress error message, while the meetings have been launched through different hosts.
Reproducible across many desktop users on Chrome and Edge latest versions, while the mobile client works just well.
Web SDK version 1.9.0.
The full error message or issue you are running into.
One single Zoom session produced three types of issues: blackout screen upon the 3rd second after the successful joining to the session across various desktop users, then it turned into a Timeout error message, then is showed Already has other meetings in progress within the developer console.