• renderer: implement native sRGB support DaemonEngine/Daemon#1687
• tr_shader: linearize fog colors DaemonEngine/Daemon#1796
• Add the linearColorMap, linearSpecularMap and linearRgbGen keywords and raw variants DaemonEngine/Daemon#1855
  Add a shader keyword to tweak legacy blend shaders to workaround their incompatibility.
• Fogs to fix in official maps #3427
  We may want to implement a different algorithm?
• Check game assets for linear colorspace compatibility #3395
  Test all maps and take actions (use the keyword mentionned above, something else).
• Redoing map levelshots #3416
  Not something to be done to implement compatibility, but to be done once compatibility is implemented.
• Update the build profiles in Urcheon.
• Rebuild all the stock maps, as part of a release.
• Re-release NetRadiant with an updated build menu.

We also have this but I don't know if we need it, I would prefer to avoid duplicating shaders, and we only need to load old maps the old way, we don't need to be able to build new maps the old way:

• Stage-level colorspace keyword for shaders DaemonEngine/Daemon#1721