Hello and thanks for Tree Tabs!
I just tried it in Firefox Nightly, and Tree Tabs doesn't seem to know why new tabs are opened, leading to them not being added as a child of the current tab. I can tell TT to place all new tabs as a child of the current tab, but this isn't fantastic behaviour when I want to start a new tree.
Is this a TT bug or firefox limitation?
Oh, and I'd love for TT to have an export tree function - possibly expanded to an automated tree backup system. I might have a bash at adding this myself if this addon was on github