Anyone got a browser running with GPU offloading?

I‘m trying to run either chrome or firefox with GPU offloading like __NV_PRIME_RENDER_OFFLOAD=1 __GLX_VENDOR_LIBRARY_NAME=nvidia firefox. I’m hoping to get better performance for WebGL pages that way. Offloading works fine for simple vulkan and glx apps on my machine.
It seems like both browsers do not work correctly with offloading (about:gpu or about:support show that webgl2 is disabled or no hw acceleration is available)
Did anyone get a browser correctly running on the nvidia GPU?

Doesn’t work, needs changes to the web-browsers:
https://devtalk.nvidia.com/default/topic/1063044/linux/prime-offloading-unable-to-run-chrome/post/5383344/#5383344