Differential.allow-self-accept is false in my phabricator:
differential.allow-self-accept
Customized
Allows users to accept their own revisions.
Current Value: false
However, a user reported that he was able to assign himself as the reviewer for his own revision. He has no option to accept it though i.e. he does not see Accept Revision; he sees Abandon Revision but that's not what he wants.
I followed his steps and was able to assign myself as the reviewer for my own revision as well
click on Create Diff
upload a file
click on Create Diff
click on Continue
enter title for revision
assign myself as reviewer
click on save