Alternative now firefox-gnome is going to die (due to firefox advanced theme support removal)

[ghost]

You can just install: https://addons.mozilla.org/en-US/firefox/addon/hide-caption-titlebar-plus-sma/

Then you put this in ~/.mozilla/firefox/cjqhvp8j.default/chrome/userChrome.css

#titlebar-min, #titlebar-max
{ display: none !important; }

#minimize-button, #restore-button
{ display: none !important; }

#close-button
{
	margin-top: 2px !important;
	margin-right: 2px !important;
	width: 24px !important;
 	height: 24px !important;
}

And it will look like this:

Not perfect but ok for me (you need to play with sma options).

Now, next question is, will SMA compatible with next firefox versions? Until?

[smichel17]

SMA will almost certainly stop working at the same time as this addon (when FF disables XUL support). The css for fixing the min/max/close buttons is nice, though, and will continue to work.