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Find and bookmark a work that has some links in its stats line (i.e. has kudos, collections, comments, multiple chapters)
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The bottom borders/faux underlines on any links in the last line of the work's stats are hidden.
It should be visible.
If you look at the CSS for the section of the bookmark that contains your notes (.bookmark .user) – the user module – you'll see there's a margin-top: 0.643em on it. However, this margin doesn't actually work because the stats line was floated in (pull request #1139).
Ergo, we probably need to add margin-bottom: 0.643em to .bookmark .blurb dl.stats to create the desired margin. (When you press "Edit" on a bookmark, the margin-top adds a tiny bit of space between the bottom of the edit form and the user module, so it should probably stay in despite being mostly useless.)
This issue happens on Windows but not Mac due to the font difference described in AO3-5526. However, there is very little space between the links' borders and the user module.