Actively manage the required GLSL/OpenGL version used by the pipeline and restrict arbitrary #version directive in post shaders for a more robust system requirement management. The ideas proposed are:

• Pipeline can request a specific GLSL/OpenGL version,
• Canvas detects the system's supported OpenGL version and hides or disable unsupported pipelines in the form of log message or a GUI element,
• #version header is provided by Canvas (or Frex) according to the requested GLSL version. Optionally, detect and suppress existing #version directive.

Note that at the moment there isn't any presented use case for this except for compute shaders.

• Alternatively Canvas's pipeline API can provide a list of optional "extended features" such as compute shaders which pipelines can request and Canvas infers the required GLSL version automatically (the rest of the points still stand).