Comment 33 for bug 1797308

@benishor: Thanks for checking it out, and confirming it works on a real hi-DPI screen.

Here is a patch to make it a real UI (you can remove the old one). Could you just check again and make sure it works as expected? Set the scale to 2.0 (or whatever your scale is) in the main preferences.

I have also fixed the OpenGL grid thickness.

@Seth: this approach calls into the config/env var stuff a lot. Should it be cached/memoised or something?

This doesn't touch Cairo, but it could in theory use the exact same interface as OpenGL.