Mobile user vs desktop user mis-match
Problem: Signed in using Android, all posts made using this user do not seem to be associated with the same user using a desktop system (specifically Firefox).
For instance; posts made by my user from an Android phone cannot be edited by my user from Firefox.
Similarly, the thread subscriptions do not match. A post made from the regular desktop site does not cause the full-site user to be subscribed to that thread and vice-versa.
In summary, it's as if the mobile and regular users are two different users, even though they share the same credentials.