Seen quite some time ago. But still present.
Steps to Reproduce:
- Watch some frequently edited page.
- Have "Group results by page" in Watchlist (or RC) enabled.
- Uncollapse some block of changes.
Actual Results:
As the screenshot shows, some of those separators are missing surrounding whitespace (red underline), whereas others do have it (blue underline).
Example from my watchlist on wikidata.org.
Developer notes
Sample HTML shows missing spaces
` <td class="mw-changeslist-line-inner"> <span class="mw-title"><a href="/w/index.php?title=Talk:Arabic_language" class="mw-changeslist-title" title="Talk:Arabic language">Talk:Arabic language</a></span>‎‎ <span class="mw-changeslist-links"><span>8 changes</span> <span><a href="/w/index.php?title=Talk:Arabic_language&curid=1069&action=history" class="mw-changeslist-history" title="Talk:Arabic language">history</a></span></span><span class="mw-changeslist-separator"></span><strong dir="ltr" class="mw-plusminus-pos mw-diff-bytes" title="738 bytes after change">+738</strong>‎ <span class="mw-changeslist-separator"></span><span class="changedby">[<a href="/w/index.php?title=User:Toby&action=edit&redlink=1" class="new mw-userlink" title="User:Toby (page does not exist)"><bdi>Toby</bdi></a>‎ (8×)]</span></td> `
Inserting a space character before mw-changeslist-separator opening tag and after it's closing tag should take care of this