Dec 18, 2015
Left 4 Dead 2 - Valve
An update has been released for Left 4 Dead 2:

- Added haptics support for Steam Controllers
Dec 16, 2015
Left 4 Dead 2 - Valve
An update has been released for Left 4 Dead 2:

- Fixed Options menu cutting off Steam Cloud option.
Dec 10, 2015
Left 4 Dead 2 - Valve
An update has been released for Left 4 Dead 2.

- Fixed some Steam Controller bugs
- Added bindings for voting with the Steam Controller
Left 4 Dead 2 - Valve
An update has been released for Left 4 Dead 2 Authoring Tools.

- Fixed Workshop Manager failing to launch.
Nov 10, 2015
Left 4 Dead 2 - Valve
An update has been released for Left 4 Dead 2.

- Additional bindings and fixes for Steam Controller support.
Left 4 Dead 2 - Valve
An update has been released for Left 4 Dead 2.

- Added native steam controller support.
- Added support for surround sound on SteamOS.
Oct 14, 2015
Left 4 Dead - Valve
An update has been released for Left 4 Dead.

- Fixed an exploit that could shut down dedicated servers.
- Fixed several buffer overflow exploits with networked files.
- Fixed a series of exploits caused by invalid or malformed textures.
Left 4 Dead 2 - Valve
An update has been released for Left 4 Dead 2.

- Fixed several security issues.
Left 4 Dead 2 - Valve
An update has been released for Left 4 Dead 2

- Fixed a possible crash when a server goes into hibernation.
- Fixed an occasional crash in the physics system when touching entities are deleted.
- Fixed a crash in scripted_user_func command.
- Fixed Survivor bots picking up weapons from a spawner that was already depleted.
Jan 23, 2015
Left 4 Dead 2 - Valve
An update has been released for Left 4 Dead 2

- Fixed an edge case where a Survivor that should have been incapacitated from taking damage would be killed instead, even though the Survivor wasn't on third strike.
- Cheat-protected some sound mixer commands to prevent exploits.
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