I was reviewing a suggested edit which I chose to 'Improve and Edit'.
Whilst editing I tend to use the Ctrl and arrow keys to jump across words quickly. I went to insert a couple of newlines with Enter, but because I was holding Ctrl this was interpreted as a 'Submit Edit'.
Normally I wouldn't consider this a problem, but would go find the question and continue the edit whilst the 5 minute edit window still existed. The problem is I hit Enter twice in order to start a new paragraph, and it seems that (looking at the revision history) it submitted an edit twice.
However, the second edit is completely blank, as seen here:
You can see the original suggested edit is revision 2, my (unfinished) improvement is revision 3, and the blank one is revision 4. It's probably showing as blank because there were no changes from the previous revision. I would've thought that a blank or 'no changes' revision would be rejected on the server side?
Here is the question in question.