Bitdefender anti-spam toolbar causes thunderbird to ark all incoming emails as read.

As per the title, this began happening the moment i added the toolbar, remove it and things go back to normal.

I can watch this in action, a new email appears in my inbox shows as unread then instantly changes to read. I have no preview pane so that not the issue. It's most definitely the bitdefender add-on doing it imo.

Is this a known error?

Thanks