Various customizations I prefer.
about:config
| What it is | Config name | Value |
|---|---|---|
| Scroll distance | toolkit.scrollbox.verticalScrollDistance | 7 |
| Print using system dialog | print.prefer_system_dialog | false |
| Prevent fullscreen exit with ESC | browser.fullscreen.exit_on_escape | false |
| Show “https://” URL prefix | browser.urlbar.trimURLs | false |
about:keyboard
New Private Window->CMD+SHIFT+N