In trying to move several THOUSAND emails from one email account (which will be shut off) to another, after we selected all emails in the old account, we inadvertently we must have asked Thunderbird to open all of those emails. I have manually tried to close these tabs (either using the x in each tab, or Ctrl-W). Nonetheless, Thunderbird is slow as molasses with this crazy number of tabs open. Is there a way to reset Thunderbird without any of these tabs open, just the main mail window? Right-clicking to close other open tabs does not respond, so I need to know how to actually open Thunderbird with just the default tab opening and now other. Thank you.