Comment 24 for bug 1966108

solution thanks to https://bugs.launchpad.net/ubuntu/+source/chromium-browser/+bug/1897454

First launch chromium with this command (only needed once) from a terminal
$ chromium --enable-features=UseOzonePlatform --ozone-platform=wayland

Then change the ozone-platform-hint setting by typing into the browser location bar:
chrome://flags/#ozone-platform-hint
And change the value from "default" to "auto"

BTW on nvidia I get loads of DRI related errors and messages about stopping use of gpu
which not surprisingly disappear if I disable hardware acceleration in the browser settings panel (system, hardware acceleration) - sad not to be able to use the GPU for chromium - sigh.

Once the ozone platform hint has been set, you can just launch chromium as normal, ie without the UseOzonePlatform feature - eg from the terminal using:
$ chromium