You need to have more than 2,000 reputation points to edit any post without going through a peer review. If 2 reviewers accept (reject), your edit will be posted (rejected).
Now, after you finished your edit and submitted it for a peer review, the OP could see the change as it is notified to the OP by a message. The OP has 4 options, Approve, Reject, and Improve Edit (suggested by you), and do nothing.
If the OP doesn't do anything and your edit is approved by 2 other users, your edit will be posted. You will receive 2 reputation points.
If the OP clicks on "Improve Edit", your edit will be reflected right under the OP's edit in the revision history and 2 rep points will be given to you.
However, if the OP rejects your edit and uses your contribution (links and changes) in his/her own edit, your display name will not appear in the revision history, nor will 2 rep points be given to you.
The OP typed "more" additionally to your edit and clicked on Save Edits and the No. 3 above happened.
It doesn't happen very often and there is nothing you can do about it. We can never know whether the OP did it intentionally or not. It could be just coincidence.
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