To quote a user;
I tried to upload a SVG file with 2 accidental errors which both make uploading the image fail: missing xmlns="..."
what bothered me was the error message: "File extension does not match MIME type." This is just uninformative and unhelpful. Could it be improved?
The user is right, I should get it to return a more useful error than that. We probably have to separate the mime checking, from the file validation error responses. We do both now in mimemagic, but the error messages only really account for MIME matching.