It shows $2 instead of the number of users in this diff:
http://gl.wikipedia.org/w/index.php?title=Wikipedia%3ASobre_Galicia&action=historysubmit&diff=1659718&oldid=1588422
The parameter $2 should be substituted by the corresponding number. The message seems to be correctly translated at translatewiki:
http://translatewiki.net/w/i.php?title=MediaWiki:Diff-multi/gl
Version: unspecified
Severity: enhancement
URL: http://gl.wikipedia.org/w/index.php?title=Wikipedia%3ASobre_Galicia&action=historysubmit&diff=1659718&oldid=1588422