Thanks for the feedback.

But you are comparing warm with red.
You estimate not expansion and the functions realized in it. You lower the estimate for the fact that this extension does not look like another. It's like saying that Fiat is a bad car because there are no Ferrari functions in it.
Now about your suggestions:
1. The function of saving the session when closing the window I am testing now.
2. At the moment I do not see a way to use containers with bookmarks.
3. Using bookmarks this can not be done. That is, you can try, but I see no reason to spend my own resources and computer resources on it. In addition, it will certainly be a source of additional bugs. In my opinion it is easier to move the mouse and click on the #9 tab.
4. So it was intended. In the view mode, clicking on a tab will switch to this tab. In edit mode, a tab from another session is added to the current session. And how should be in your opinion?