It doesn't look like id Software has dropped (or otherwise revised) any new major code, but rather they have consolidated all of their open-source efforts on GitHub. Hosted from this GitHub area is now the source-code for Wolfenstein 3D for Apple iOS, DOOM Classic for iOS, the original Quake GPL, the original DOOM, Quake-Tools, idsetup, Quake-2-Tools, GtkRadient, the Doom 3 GPL release, Enemy Territory, Return to Castle Wolfenstein Multiplayer GPL, Return to Castle Wolfenstein Single-player GPL, Quake 3, and Quake III Area. Each of these titles have their own Git repository on GitHub.
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