Valve released an update on October 5th with fixes for image judder after long periods of play, audio glitches, and some seasonal map quests. The patch is applied after restarting the game.
Fixed enabling the Marshlands contract and tracking targets with a train, saw or laser on the TrainSawLaser. For community servers, the sv_wallbug variable has been added, allowing you to return the previous movement behavior. This is a server specific setting, so movement may vary between communities. When re-checking the contract, make sure that the client is updated and the appropriate card is selected.
Sources and checks
Team Fortress 2 Update Released · Steam
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