Is it possible to hide the tabs area at the top of the browser?

[BrianGilbert]

So that only the Sea Containers Sidebar is visible, and you can only access tabs via it.

Tree Style Tabs manages to do this currently (not sure if it's because it's still using legacy things though) https://github.com/piroor/treestyletab

[BrianGilbert]

Sorry I just saw that this is in the readme..

In case anyone finds this issue:

Firefox lets users override 'chrome' level styles. Add a chrome directory and create a chrome/userChrome.css file with the following contents and then restart firefox:

@namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul");
#TabsToolbar {
  visibility: collapse;
}