Github (and other sites) monospace fonts aren't actually monospace as of 92.0
In the attached image, the code is indented with 4 spaces, but it displays as if it's 2 spaces because the spaces are thinner than the other characters. In the second image, I've highlighted a single space, which is half the width of the character above it. I also downloaded the latest nightly and this still happens with it.
Github's current `font-family` rule: `ui-monospace,SFMono-Regular,SF Mono,Menlo,Consolas,Liberation Mono,monospace`
In devtools, firefox underlines `Liberation Mono` as the active font-family, but I uninstalled that from my system and it switched to `monospace` (Noto Sans Mono) with the same issue. If I change it to remove the `Consolas,Liberation Mono,` it gets fixed, but when `Liberation Mono` is installed+highlighted and I only remove `Consolas,` it doesn't work til I remove `Liberation Mono,` as well. Note that both `Consolas` and `Liberation Mono` resolve to "Noto Sans Mono" "Regular" in fc-match, which is my default monospace font.