See https://bugzilla.mozilla.org/show_bug.cgi?id=1511726

Assuming you're on non-Windows, the message is expected and not indicative of a problem. I've pushed a patch to disable it going forward. Sorry for the noise.

Thanks for the pointer. May be still display something but like "shader cache is not used" so it will be clear that the feature isn't utilized yet.

This is talking about webrender's on-disk shader cache for the shaders it itself is deciding to cache, not your GPU driver's shader cache.

Looking at https://searchfox.org/mozilla-central/rev/adcc169dcf58c2e45b... it looks like that error means the disk cache was not created.

So either get_cache_path_from_prof_path failed to return a path or create_dir_all failed.

I haven't dug through more details, but I'm pretty sure the shader cache code there is new and am not at all sure it's completely hooked up yet.

because you're on a beta build?

Why would beta build not find shader cache?

Beta == unfinished, may have bugs.

No, "beta" means "finished, but may have non-show-stopper bugs".

If it's not finished it's alpha.

Beta is pretty much just used as "buyer beware" nowadays, like a disclaimer "we take no responsibility for our bugs".

Offtopic for sure, but the way most places I've worked have used the terms is: "alpha" means that the developers think it's done. "beta" means QA thinks it's done. "release" means that actual user testing revealed no showstoppers.