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

Left 4 Dead Demo

• Tuned matchmaking to provide better search results
• Added UI to host a game on a local server
• Improvements and performance optimizations to network layer
• Improved handling of unsupported graphics hardware
• Fixed a rare crash when kicking people from lobby
• Fixes for demo exploits
• Localization fixes
• Increase automatic port range when running a Linux dedicated server with -fork

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