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This type is already 2 weeks as fixed, along with some important fixes. Please check the version of your extension, it must be 1.4.130, if not - then you have a problem with Chrome autoupdate.

Well, need to say that I am very rarely collapse anything in the tree. The collapse feature in this program is mostly used as a step before deleting some hierarchy, with all the nodes inside, not to organize content. So, I never experience the issue you mention. But I, of course, see how this might be really a problem for some users. I will add this item to my internal to-do list though I cannot promise any release date for this, yet if this is something easy to implement I will do it.

There many more of such examples, but they all modify the page content to accomplish this. this is have so many drawbacks that it's not an option for this project. There is now in development Sidebars API by Chrome team (or at least it's marked so in there issues databases) when support for real native sidebars will be available it will be utilized.

As for using the Tabs Outliner in the in-page sidebars, maybe exist some extension that can create sidebar for any page (like Tab Resize or Panel Tabs, but they do so in panels), then it will be possible to load the Tabs Outliner interface in such sidebar, provided and managed (and collecting all of the negative feedbacks because of the all accompanying problems) by other extension.

Hi, can you please describe steps to reproduce this problem more more precisely? I cannot understand and reproduce this issue meantime.

Both of this proposals is not what most users expect from such functionality.
The search just must search inside collapsed nodes also, and such functionality I hope to implement in near future. And maybe I will add something like Alt-Ctrl-+/- as a shortcut for Expand/Collapse All.

Really, meantime collapsed nodes is not first class citizens in Tabs Outliner, to fix that need much more work than just a few shortcuts.

It's actually always at the bottom of the screen regardless of how many tabs you have : )
Seems they do not have a shortcut, need to fix that, but the '-' and '+' keys works to expand/collapse a current node (in the paid mode).