Updates to Left 4 Dead 2 Demo have been released. The updates will be applied automatically when your Steam client is restarted. The major changes include:

Left 4 Dead 2 Demo
Fixed bug that caused dedicated servers to become unjoinable over time without a restart or heartbeat update
Fixed exploit that allowed players to end a campaign and return to the lobby without a vote
Public players are no longer matched to lobbies that are idle for a prolonged period of time. These lobbies become "Friends-only" lobbies
LAN servers list will now show listen server single player games as not joinable and will show game type as "single player" too
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