Editing pasted images doesn't work as expected
If you paste an image from the clipboard then go back and edit the post by select-all and then paste again you end up with both images. Repeat ad nauseum.
You have to select-all and then delete before pasting again.
Not earth-shattering, but a bit annoying.
Edit: reproducible in the composer for a new post/reply too.
That's because when pasting an image the composer deselect and moves the cursor to the end (IIRC).