Add a + icon to the container to open a new tab instead of clicking on the container name

[timkgh]

Clicking on the container name to open a new tab is not intuitive and in fact annoying. I want to click on the container name to activate the expanded container not to get a new tab.

Having a + icon next to the focus icon would make more sense.

Users also know how to use Ctrl+T / Cmd+T to open a new tab when they need it.

[metastable-void]

Maybe that makes sense, though when we change things prior users need to be notified properly of the new behavior (i.e. with some tooltips).