У вашего броузера проблема в совместимости с HTML5
Platform: PC
Difficulty: Expert
Campaign: The Parish
600 Hell Mutation - No zombies, but hundreds of Special Infected (less than 600). At first, you will get AK47 and magnum, no weapon was banned, and you might run out of the ammo. When you're down, you only have 1 HP (die very soon). Tank only have 1000 HP.
Steam: http://steamcommunity.com/profiles/76561198086346896/
Discord: https://discord.gg/mUmMfZJ