Greetings from Fyde Innovations.
A few years ago there were several projects to port Chromium OS onto Raspberry Pi, some of which got merged into the upstream official repository. However it seems they didn't attract too much attention from either the Pi / CrOS community over the years.
I'd like to introduce one of our actively maintained open source projects - Chromium OS for Raspberry Pi. Github link for source code and BIY instructions here
If you are only interested in the pre-built image, look out for the public releases:
https://github.com/FydeOS/chromium_os_f ... i/releases
Today we have just pushed a new release for Chromium OS v70 to work with Raspberry Pi 3B / 3B+, with updated documentation and a pre-built binaries.
I hope this can help anyone who wishes to run Chromium in a more graphically efficient way. If anyone is interested in picking up the development of Chromium OS for Pi, this may be another source of reference.