3. if you've got more than one image, then the field for entering text for an image description is fucking tiny!!!!!! why!!!!!!!! (see image)
so to condense my suggestions into one holistic solution
how bout, you click the image to add a description, it opens the image up full res with a big honkin' old text box underneath. and if you change tab or whatever then it all stays there on screen exactly how you left it until you click OK
masto accessibility request 3/3 Show more
@Murkrow extremely impressed if you did this toot (including caption) on mobile