There's no pill/button in the window title bar that you can click to hide the toolbars in Cocoa Firefox.
I don't see anything in the Cocoa API that might allow us to do this. It looks like up until 10.4 that button's appearance was automatic, and in 10.4 there is an API but it only affects the window if your window has a native toolbar.
I don't see it in Cocoafoxen on 10.3.9, either, though.
I have a patch in my tree I need to clean up that fixes this. It uses two private methods on NSWindow that don't look terribly invasive to override. (BOOL)_hasToolbar; (void)_toolbarPillButtonClicked:(id)sender; I found them while poking around with F-Script on something unrelated.
Created attachment 264200 [details] [diff] [review] fix v1.0 Here is the previously mentioned patch.
Comment on attachment 264200 [details] [diff] [review] fix v1.0 mento, can you review this instead, since Josh seems overloaded on other things?
Comment on attachment 264200 [details] [diff] [review] fix v1.0 Have you tried this out on a Lep seed too?
Comment on attachment 264200 [details] [diff] [review] fix v1.0 sr=mconnor, please get this landed ASAP
widget/src/cocoa/nsCocoaWindow.h 1.33 widget/src/cocoa/nsCocoaWindow.mm 1.89 Having to check in fixes for my own bugs sure beats having to fix my own bugs :)