-e: when selecting Linear color space there should be a hint that you need to remove WebGL 1.0 from the API list and you should not be able to start a build

-repro:
--open new Unity project
--switch to WebGL
--go to player settings
--switch color space from gamma to linear
--notice error being shown
--start a webgl build
--NOTICE it starts and succeeds while it should not be possible and telling you about the graphics API mismatch