Undo Twitter's insistence to down-res images when viewing on its dedicated page and add a button to download the full image without the weird file extensions which don't count as actual images.
Per
Retrieves the original resolution image from Twitter, once the image has been viewed directly through its URL (usually via right-click -> Open image in new tab). Also adds a button to download the image (on said page), automatically renaming it to the proper file extension (as opposed to .jpg-large which is due to Twitter's abuse of URLs).
