It's usually fairly easy to edit the text of a post you made on Facebook — you simply click the button on the upper right area of the post and it offers you the option of "Edit" or "Delete". However, if you've added a photo and you then try to edit the text, your option is only limited to whether you wish to alter or delete the photo. The option to edit text is not offered.
Any way around this?
Click on the photo to bring it up, then use the edit function within to edit the text rather than the photo
You are correct that it's not possible from the news feed. (Currently.)
However, this is possible from either your timeline view:
Or by clicking on the image to expand it to the theater view:
Or by somehow (from the theater view, click on the posting date) ending up on the old-style photo page:
However, I expect this will change and editing will be possible from the news feed. Facebook is currently undergoing a change to allow better editing of content. A while ago only comments would be able to be edited, not posts. Currently posts can be edited as well. I expect not being able to edit photo items (which nowdays look and behave a lot like posts) from the news feed is just a leftover behaviour that will be fixed.
