After the extender is reset, everything goes to the out-of-the-box defaults; username and password both "admin". The updated firmware is maintained, so you do end up where you wanted to go. It's just...

There's no way to create a new password, and neither "admin" nor the password I previously changed it to works. The window says simply "enter password" and gives you a field to enter it into. There...

Still very much a thing ... I have two of these and it was the same for both. Resetting and reconfiguring does work, but it's a pain and shouldn't be necessary!