evolution asks for the username/password for public web calendars on reconnect.
I added a web calendar from a website that does not require authentication. upon automatic refresh, evolution failed due to connection issues and offered to "reconnect". the reconnect dialog wanted a username/password. This was even before the connection came back so evolution had no way to tell if there was 403 error and just assumed one. There was no username/password when the web calendar was added.
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