Improvur is a Firefox extension that rewrites Imgur links to point directly at the target image file when possible. For example, a link like http://imgur.com/yeAzeso will be converted to https://i.imgur.com/yeAzeso.jpg. This allows you to view the image file without loading all of Imgur's social content, advertising, etc.
Gallery and album links are left untouched, since they need Imgur's scaffolding to work properly. Also, links on imgur.com itself are not rewritten so that features on that site continue to function as intended.
Links are rewritten to use a .jpg extension regardless of the actual image type. This works because Imgur generally ignores file extensions and serves files based on their MIME type instead.
- Improvur works with Firefox versions up to 56. Unfortunately, Mozilla has rendered many extensions obsolete by moving to WebExtensions. I may look at converting Improvur in the future, but it's not a priority.