After restarting Firefox, all tabs previously sorted in many groups are in Ungrouped. All informations about tabs in groups are lost. Sorting tabs into groups has already been specified for add-on. There is no situation for the add-on to lose this information. Add-on has poor session management and is unreliable. It is very frustrating for the user to reorder all tabs into groups again and again...

After some time, about 80% of the pages on other tabs were lost. The plugin has **absolutely unreliable** status information management.

Has a very annoying feature; once in a while it loses tree structure when ff gets restarted.

When I create a series of groups, arrange my tabs into the groups as desired, export the session and later import the session (all on the same computer/browser), all of my groups are present with "0" tabs. All of my tab arrangement has been obliterated and all tabs are moved back to the "Ungrouped" group. Huge waste of time making the session export/import functions pointless and this extension unusable.

Removed EVERY of my 350 Tabs except the 5 pinned ones, no way of restoring them, forgot it's own settings (colors, which buttons, ...). It's very dangerous to use something unstable like this productiviely. I came from Tree Style Tabs - but at least they always worked. I'll use a better Tree-Tab-Addon in my company now (5 clients).

Why does it need to 'Access your data for all websites'?

Avoid Tree Tabs. This so-called extension has no functions at all. There is no interface, no options, no access to content, nothing. So, as to its purpose - none. It simply does not have any.

When trying to install this add-on, Firefox 56 says the add-on is corrupt.