Updates to Portal, Half-Life 2, Half-Life 2: Episode One and Half-Life 2: Episode Two have been released. The updates will be applied automatically when your Steam client is restarted. The major changes include:

Engine
Fixed fonts sometimes not displaying when the game is loaded (Mac)
Fixed crash on launch in rendering subsystem (Mac)

Portal
Optimized particle rendering for lowend GPU's, made acid pits more performant (Mac)
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