Right after I posted my previous comment I googled and found a solution for the folder view switching. There is an extension available that provides it now. It's called "Folder Pane View Switcher" and it works just fine. I provide a URL below but it's not needed if you use the thunderbird add-on manager to download and install it.
https://addons.mozilla.org/en-us/thunderbird/addon/folder-pane-view- switcher/ -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/990331 Title: Big Thunderbird problems after Ubuntu bugfix update To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/thunderbird/+bug/990331/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs