Isn’t there a middle where you don’t show the whole browser chrome by default and still allow access to the extensions? Maybe add a tiny button to show the browser UI or add a shortcut?
That is how it works in Chrome, right? Or am I going insane? When I open a web app I made with Chrome, there's a small icon in the top right of my window that opens the extensions dropdown.
From the Connect post I gather that a middle ground is basically the plan - you'll still have e.g. your extensions accessible, but there won't be a tab bar.