Piro’s TST solution is working well for me.

What I wanted is a visual way to capture my trail as I browse, and that’s what it does. Attempting to try to turn it into tab organizer tends to lead to frustration. I find that a useful constraint—otherwise I’d be organizing tabs all day instead of researching things.

I put TST sidebar on the right, I use “Right side” style of contents, and RTL text direction. Even though I generally browse in English, the general alignment of things with these settings appears to work best for me so far.

I provision custom user chrome CSS in my Firefox profile (hopefully this keeps working) to hide the now-redundant default FF horizontal tab bar and TST sidebar header. I also used TST’s debug mode to tweak a bunch of settings and added bits of custom TST CSS to achieve the desired look & feel (samples in TST’s GitHub repo were a useful starting point).

I use TST with Conex, switching between containers and only showing tabs from currently selected container. I believe I had to fiddle with TST settings a bit to make it work together with Conex smoother, otherwise tabs within the same tree were opening in different containers. (I think it is not TST’s problem that with default settings visual hierarchy gets messed up if tab hiding is on.) In the end it’s hard to keep track of my tweaks and which of them are relevant as the extension gets updated, but it works nicely now.

I wish for an easy way to dump a tree of tabs into bookmarks while preserving the hierarchy in some way (even if it doesn’t let me restore the tree). The primary challenge appears to be that in Firefox a bookmark folder can’t itself be a bookmark, while in TST a tab holds other tabs.

I do encounter a situation where after Nightly’s update & restart, the TST sidebar never gets loaded. Just quitting the browser and opening it again fixes that. So far I haven’t lost tabs and never had tab hierarchy mess up on me, even though I was using pre-release TST builds from GitHub for a while until 2.4.20 came out.