The URL should be added unconditionally to the result from wbsetsitelink to avoid a second call from the UI to the wbgetitems action.
The fix is rather trivial, its only necessary to add the options params to addSiteLinksToResult at line 129.
Version: unspecified
Severity: normal
See Also:
https://bugzilla.wikimedia.org/show_bug.cgi?id=40074