Canvas / WebGL proper DPI / scaling on 4k screen

So, friend of mine took this side by side on 4k screen

LibreWolf - left | Firefox - right Watch image with 100% zoom directly (LMB), in issue it's little smaller

For web-designers that is a big problem.

If you look on top darker line and it's fonts - they're identical (usual html / css), however when you look down at <canvas> with Figma stuff...

LibreWolf renders this canvas clearly without being DPI aware

I assume there should be some fingerprinting related breaking setting for this to happen, something WebGl / Canvas / General screen size or dpi related...So final rendering have no idea on actual screen DPI / OS scaling or something of that nature.

We need to find those settings and document them