Fixed the game starting in the top left corner of the screen on Linux. Fixed the intro videos for acts 2 and 3 not playing on Linux. Fixed the credits being corrupted on Linux. Fixed a crash that could occur in some community test chambers using BEEMod on Linux. Fixed a crash on startup that could happen on Linux. Removed the 'Trading Coming Soon' button. Added the ability for workshop levels to pack particles into their map with a particles/map_manifest.txt Improved client-side prediction for coop play. The portalgun is now correctly affected by dynamic lights (projected textures) in the scene. Button text contrast and padding has been improved when using a controller. Players can now be invited to play co-op on controller. Improved resolution of player avatars throughout the game. Improved advanced video settings descriptions. Improved compile time for Perpetual Training Initiative puzzles. Implemented a Vulkan render backend (currently accessible through the -vulkan command line parameter). An update has been released for Portal 2.