avatar cropper

It would be good if users could make simple avatar images edits, such as changing size and position, cropping, etc. I don't know if there is any add-on for that. I searched but found nothing.

Firefox 68.0.1, Windows 10 (1809) Avatar Cropper is "antsy" when i try drag image. I can't explain this, so i attached a video, where this "behavior" is seen.