A good feature which can be made better: 1) Sync opened tabs in different container across devices. 2) Send a normal tab to a container and close the original tab (currently it reopens in a new one in the designated container and so you result in having 2 tabs). 3) Make hiding a container easier (e.g. by right-clicking on the tab and have a option in that menu; currently users have to click on the add-on icon, click the tiny arrow of that container, and then click hide).