Regarding the mysterious picture adds/replacements. I caught this problem in mid post that might give some clues to what is going on....
I am entering in a new post. I add a picture. In this case it is a picture of a mushroom in a photography focus stacking thread. I do the usual and add the pic, the post has not been sent.
In another window, I then scrolled through my old posts to find one that I intended to link into the post that is still open.
My eye caught that the pic of the mushroom had been substituted for a post of a graph in a corona virus thread - literally added to the post and when viewing the post, I can see that it was added and I could also see a notice:
There are attachments found, which you have attached before but not posted. These attachments are now attached to this post. If you do not want to include them in this post, you can remove them here. So leaving an unattached photo (as when you are writing but have not submitted a post) is fair game to be inserted into any of ones posts that you view (not modify). Sounds nutty, but it looks like that is what just happened. I will complete the post and edit this message to see if it changes.
EDIT: as you can see, the pic in "limbo" got attached to this post. I did not add it to this post as per normal. Now that I know, I will be sure to have all my pics for a post lined up before opening any other windows or doing any other actions.
EDIT: I also see that the mushroom pic remained added to the corona virus post and bumped the original pic. I had to 'hand' correct that.
EDIT: and further, while the thumbnail pic attached to this post is the mushroom, the pic after the thumbnail is clicked, is the graph from the corona virus thread that I had to replace. I will log off hopefully clear the cache
du jour and see if there is persistence....logging off/on makes no difference.
Pics in limbo are evil and get put in places that you don't want. Orphaning pics is the devils work