Official notes checked through 1.0.9; third-party gameplay not re-tested
01
First, identify the exact black screen
The official patch notes discussed a black screen while joining a lobby separately from a gray-screen startup problem. Record whether the menu appears normally, whether audio continues, and whether only the joining player is affected.
Joining-lobby black screen: the menu works, but the transition into a friend’s session does not complete.
Startup or gray screen: the failure begins before the normal menu and belongs in a different report.
Host-wide failure: every joining player fails, which points to a different reproduction pattern than one affected client.
02
Retest without hiding the evidence
Update the game, restart Steam and confirm the session type. Then check whether the Steam Relay status turns red before attempting one controlled retry. Community workarounds should remain optional, clearly player-reported and reversible.
Capture the game version for the host and joining player.
Restart Steam on both PCs and confirm the same lobby type.
Record the main-menu Steam Relay result.
Retry once, note the time the screen turns black, and record whether audio or controls continue.
Send those details through the official support route if the issue repeats.
Source locker
What supports this route
Every source has a job and a limit. Community reports remain leads, not universal facts.