On the https://joeyh.name/ ikiwiki preference page I added an e-mail subscription PageSpec. Now when I view the preference page the PageSpec field is empty, but I'm still getting e-mails.
My guess at the cause of the problem is that I created an account using the e-mail login, then registered another account with a username. I think now when I login via either method I'm accessing the account with a username, while the e-mail only account has the PageSpec for the subscription.
The e-mail notifications including a link to http://joeyh.name/ikiwiki.cgi?do=prefs but they could include a login token so I can access the page and edit the PageSpec.