There's already a bug in Fossil linked to IP changing for the same user, leading to anonymous posting, so relying on IP doesn't sound lik a good idea. Adding the User-Agent just compounds the risk of forked identity, if replying from several computers or devices (destop, laptop, phone, tablet, etc...). BTW, the forced-logout was not to disable anonymous as I had hoped, since your post (whoever you are) is **anonymous**! Probably for the *Display Name* change. Oh well...