Open this link and inspect any collapsed lines.
https://en.wikipedia.org/wiki/Special:RecentChanges?hidebots=1&hidepageedits=1&hidenewpages=1&hideWikibase=1&hidelog=1&enhanced=1&urlversion=2

Example:

• 22:24 Category:Midtown Manhattan (2 changes) . . [ Ser Amantio di Nicolao (2×) ]
  • 22:24 . . Ser Amantio di Nicolao (talk | contribs) (3 Park Avenue removed from category, this page is included within other pages)
  • 22:23 . . Ser Amantio di Nicolao (talk | contribs) (Lexington Avenue added to category, this page is included within other pages)

Compare it to grouped lines for ordinary edits, and notice "(cur | prev)" are missing even though diff links for non-grouped category changes are available at the end of each line. Also there are no history links, and title and curid in the permalinks (timestamps) are wrong (title is that of the category and the second curid is same as the first—this part being tracked as T270774).

So it should be more like:

• 22:24 Category:Midtown Manhattan (2 changes) . . [ Ser Amantio di Nicolao (2×) ]
  • 22:24 (cur | prev) . . Ser Amantio di Nicolao (talk | contribs) (3 Park Avenue removed from category, this page is included within other pages) (hist)
  • 22:23 (cur | prev) . . Ser Amantio di Nicolao (talk | contribs) (Lexington Avenue added to category, this page is included within other pages) (hist)

with

• "cur" and "prev" diffs
• "hist" link
• correct title
• correct curid

See also the corollary T148533: Categorization in watchlist different in nongrouping mode: "(diff | hist)" are plain text and no links.