A build check warning in the area "Realtime conformance". A warning: the game still publishes, but fix it when you can.
The build check runs on every game LobbyLab builds, and each problem it finds has a stable code, the exact message, the file and line when it names one, and a link to this page.
What the check looks at
Realtime games get a simulated match: every player joins, the host starts, smoke intents and inputs play for about 6 seconds of ticks, and one player disconnects and comes back. tick must be synchronous, total and within its time budget.
How to fix it
Do not end the session when a match ends; show results and offer a rematch.
Keep tick cheap and total, return plain JSON under the size limits (state 256 KB, a view 32 KB per frame), and never end the session when a match ends.
See also: every error code, the API reference and the docs.