@ArthurTheHard Try tapping the small “ALT” badge on the image (usually in the bottom-left corner). Once the text pops up, you should be able to select and copy it. If you don’t see the badge, open the image in full screen first.
@ArthurTheHard You don’t have to rewrite it. If you open the image and check the ALT text (or image description), the full prompt is there. You can use it as is.