Hazarding a guess: Not use linux

I've never had webgl work on linux (not that I've tried particularly hard)

I'm on OSX. I tried some different flags but I've obviously missed something.

/Applications/Google\ Chrome\ Canary.app/Contents/MacOS/Google\ Chrome\ Canary --no-sandbox --enable-webgl --enable-experimental-webgl

It's working fine for me on the beta channel without any experimental flags enabled.