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

Left 4 Dead 2
Fixed performance problem when rendering lots of decals, notably when fighting tanks with shotguns
Fixed rcon response not working on Linux dedicated servers
Fixed matchmaking problem matching into Advanced and Expert games
Fix bug that would cause other specials to try to pummel a player a Charger disconnects or reconnects
Fixed versus mode results panel being cut off in transition stats screen in non-english
Found games: fixed non-player entries drawing the wrong type of icon in the selected item name label
Game mode selector on main menu now takes keyboard input
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