I am editing an article on Wikipedia.
A warning tells me that I am not logged in and invites me to log in.
I click Se connecter, to log in.
I log in.
I am now logged in. I have my edit in progress. I can continue my edit.
I am now logged in. But Wikipedia has lost the edit I had started, and Wikipedia did not even warn me about that!
This is data loss.
This bad experience discourages the user from editing.
It would be very nice to correct this bug.