Make a compact toolbar option

[slemmy]

I want an option to make the toolbar more compact. There was one before the redesign, but now I only have the option to make it bigger. I prefer how Firefox looked before the redesign.

[wally314garcia]

Please vote for the idea "Allow resizing of the UI" that has made it to 'In Review' so the developers see that there is demand for it.

https://connect.mozilla.org/t5/ideas/idb-p/ideas/status-key/investigating

[jscher2000]

There is a secret hidden way to add "Compact" back to the Density selector. More info:

• https://support.mozilla.org/kb/compact-mode-workaround-firefox 
• https://www.userchrome.org/firefox-89-styling-proton-ui.html#compactmode

But something more discoverable certainly would be welcome.