If an svg is animated, that fact is shown in the image metadata box. However its not really formatted very well. Furthermore, all other animated formats we reflect this fact in the little subtitle under the image, not the metadata box. I think we should do that for svgs.
Additionally it doesn't seem that the metadata box respects metadata-fields message properly.
This is probably all my fault back in 65c27ddeb19757cb8a335b097039f8aeb981013e