When editing translations via (e.g.) https://translatewiki.net/w/i.php?title=Special:Translations&message=MediaWiki%3AWikibase-item-summary-wblinktitles-connect I get the following message with a wrong encoding:
["Die folgenden Parameter sind unbekannt:\n\u003Cstrong\u003E$2, $3\u003C/strong\u003E"]
Version: unspecified
Severity: minor