I improved this suggested edit while working from the new beta review queue. I'm not sure of the exact timing, but I suspect that the edit was approved (at 21:53:02) by the second reviewer while I was editing; going by my activity history, I submitted my edit between 21:51:36 and 21:57:37.
I'm absolutely sure I submitted my edit before 22:16:33 when the question was migrated.
Where did my edit go? It appears neither in the question's history (which is still sitting at revision 2) nor in my activity¹.
I was operating from the new review queue, so when I pressed
Saved Edits, I was teleported to another suggested edit. I went to my activity page, because I wanted to vote to migrate the question, but it wasn't there. I thought there was a cache effect, so I waited a bit, but when I saw other edits turn up in my activity, I searched the question on the site, saw that there was no trace of my edit, and came to meta to report the bug.