(Pro feature) Shader Stripping flags are available on a per-material basis. This is an advanced feature for larger projects I recommend touching only if you know what you are doing. It provides hints to the shader stripping process during the build process to optimize the build size and memory of the shader. For example, if you have Fog enabled on a project-wide setting, but then know that fog is not needed on a certain material, you can select Fog Disabled and the fog variants for that material will not be generated. If an incompatible setting is detected, an error color will be output. It's a good idea to make an actual build to verify the results when using these stripping flags, as they only work on builds. That said, on a major project, these flags can help squeeze every ounce of performance.