Right now, "Restore" both restores the session, and deletes it from the sidebar/bookmarks. The little "..." icon offers an alternative "restore & keep" action. I find this counter-intuitive: I frequently forget that "Restore" actually means "Restore & delete". I suggest that "restore & keep" is the more sensible default for the most prominent action, since it does not run the risk of deleting data. A default-off option to change the behaviour to delete could perhaps satisfy those who want this. (I could have sworn that "Restore" did not delete the bookmarks when I first started using this plugin.)