Please have a look at http://fr.wikipedia.org/wiki/Utilisateur:Korrigan/bug9
A SVG renders only partly, depending on the size it is thumbnailed at. This is annoying as below 300px it renders incompletely and thus cannot be inserted in articles.
It may be an issue with patterns but in any case it makes SVG usability poor.
Thanks for having a look at this.
See also upstream: