Looks good! Biggest appeal for me is that it provides dark mode without needing to use a third party webapp or a CSS customization extension with broad permissions requirements.
Some things I noticed: changes to the font size/width/line height don't seem to persist between the comments page and the front page. On top of this, the bars don't have clear numerical values so it's hard if you make any tweaks on them to match the settings across pages. ALSO I got kind of out of hand with those settings (line height in particular) and wanted to return to the default, but there's no reset button as far as I can tell.
Some things I noticed: changes to the font size/width/line height don't seem to persist between the comments page and the front page. On top of this, the bars don't have clear numerical values so it's hard if you make any tweaks on them to match the settings across pages. ALSO I got kind of out of hand with those settings (line height in particular) and wanted to return to the default, but there's no reset button as far as I can tell.