I have what programmers call: "a workaround fix".
here's what you do... your scenario of being in a thread when you aren't logged in.
when you are in the thread, and want to login without losing your place:
1. your browser menu, select file->new window.
2. login using the new window.
3. switch back to the first window and hit 'refresh'.
another tip free of charge from your friendly forum dweeb.