it is possible, but it breaks the system.

the forum is meant to be post/response/counter-response 'thread' and changing your name would make all those posts in reply to you will look rambling about someone who does not even exist on the forum!

so, technically it is possible; but not feasible.

similarly, i received a request to delete their username and delete i did; but the name will not go away; it is just that the user will be unable to login and post.

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from an individual's point of view, "just me" it may look unfair, but from the perspective of the forum, the community, it should be that way.

PLEASE DO NOT REGISTER AND POST IF YOU WISH YOUR POSTS TO BE DELETED IN THE FUTURE.