While Valve didn't seem to publicly celebrate their 30th anniversary, they did at least go back to some older titles to fix them up. Read the full article here:

Steam News · Aug 24

Half-Life Deathmatch: Source Update Released

An update to Half-Life Deathmatch: Source has been released. The update will be applied automatically when you restart Half-Life Deathmatch: Source. The major changes include: Security and stability improvements Fixed a bug where certain custom maps would not load assets correctly on Linux

Steam News · Oct 8, 2019

Update Released for Counter-Strike: Source, Day of Defeat: Source, Half-Life Deathmatch: Source, Half-Life 2: Deathmatch, and the Source SDK 2013 Base

Updates for Counter-Strike: Source, Day of Defeat: Source, Half-Life Deathmatch: Source, Half-Life 2: Deathmatch, and the Source SDK 2013 Base have been released. The updates will be applied automatically when you restart the game. The major changes include: * Various stability and security updates; * Fixed NPCs not blinking; * Fixed being able to switch weapons while holding a primed grenade;

Steam News · Feb 4, 2016

Update Released for Counter-Strike: Source, Day of Defeat: Source, Half-Life Deathmatch: Source, Half-Life 2: Deathmatch, and Source SDK 2013 Dedicated Server

A mandatory update for Counter-Strike: Source, Day of Defeat: Source, Half-Life Deathmatch: Source, Half-Life 2: Deathmatch, as well as the Source SDK Base 2013 beta branch has been made available. The patch notes are below. * Fixed a security issue related to the file system (thanks to Simon Pinfold for this report); * Fixed mp3 sounds causing occasional hitching and framerate stuttering; * Fixed...