Wikimedia appears to be using RSVG 2.14.0. In bug 14896 Tim Starling comments that the issue can be resolved by updating the package to 2.22.2.

From IRC:
[13:12] <siebrand> TimStarling: what made you say https://bugzilla.wikimedia.org/show_bug.cgi?id=14896 "appears to be fixed"? (Hidden SVG layers should not be rendered). I still see the black border in the sample rendering on http://commons.wikimedia.org/wiki/Image:Mood_dice.svg?action=purge
[13:28] <siebrand> TimStarling: re SVG 2.14.0 vs. 2.22.2: does making an update request make any sense?
[13:29] <TimStarling> I already tried
[13:29] <TimStarling> spent like an hour on it
[13:29] <TimStarling> you can make a request if you like

Version: unspecified
Severity: enhancement