Maybe there's something funny going on with your graphics stack? I think WebRender got enabled by default in 91/92, it's possible that draws in a different way.
I doubt WebRender itself is to blame (though it's possible) - there is so much other stuff that can go wrong with the layers of graphics code between a browser and your screen, and GPU drivers and differences in text rendering between different methods would be the first thing I'd suspect.
I doubt WebRender itself is to blame (though it's possible) - there is so much other stuff that can go wrong with the layers of graphics code between a browser and your screen, and GPU drivers and differences in text rendering between different methods would be the first thing I'd suspect.