On enwiki it's reported a particular edit is not showing up in watchlist but both edits before and after it are shown. It does look odd, and I tried many ways but can't find where the problem is. At [[ https://en.wikipedia.org/wiki/Special:Preferences#mw-prefsection-watchlist | Special:Preferences#mw-prefsection-watchlist ]] an option to "Expand watchlist to show all changes, not just the most recent" is enabled. I also tested it on mobile device, where option to show only the most recent changes doesn't even exist.
**Steps to reproduce:**
1. Add [[https://en.wikipedia.org/wiki/Llanelli|en:Llanelli]] to your watchlist
2. Enable "Expand watchlist to show all changes, not just the most recent" on [[ https://en.wikipedia.org/wiki/Special:Preferences#mw-prefsection-watchlist | Special:Preferences#mw-prefsection-watchlist ]] , (if you've not already)
3. Go to your watchlist
**Expected behavior**
1. These 3 edits should show up on Special:Watchlist. 1. [[https://en.wikipedia.org/w/index.php?title=Llanelli&diff=873342547&oldid=873342253|Revert of the particular edit]], 2. [[https://en.wikipedia.org/w/index.php?title=Llanelli&diff=873342253&oldid=873244656|the particular edit concerned]] and 3. [[https://en.wikipedia.org/w/index.php?title=Llanelli&diff=873244656&oldid=873177310|the edit before it]]
**Current bahavior**
1. Both 1 and 3 show up. The intermediate one does not.
On mobile, you cannot choose to be shown only the most recent changes, all pages to a page are shown. But the particular edit is not shown there too. The edits before and after it are.