Nav.post-controls with show-replies is overflowing at certain widths

It looks like this issue is related to using higher zoom levels and/or the Firefox about:config setting of layout.css.devPixelsPerPx = 1.1 . I also use an OS level text scaling factor of 1.1, but I don’t think that Firefox obeys that, which is why I have to apply the same hack to Firefox’s about:config . Here are some other layout issues I found related to the zoom level: