LibreWolf

install

# Arch
sudo pacman -S librewolf
# Windows 10
scoop install librewolf

LibreWolf
- Settings
  - LibreWolf -Browser Behavior - Enable Firefox Sync (On) - Allow userChrome.css customization (On)
    - Useful links
      1. Open user profile directory.
      2. Create chrome/userChrome.css.
      3. Copy from https://github.com/gnuunixchad/dotfiles/blob/master/.mozilla/chrome/userChrome.css.
  - General
    - Network Settings → Settings → No Proxy¹
    - Tabs
      - Open links in tabs instead of new windows (On)
      - Show an image preview when you hover on a tab (On)
    - Browsing
      - Enable Picture-in-Picture video controls (On)
More tools → Customize Toolbar → Density → Compact.
Address bar → about:config → toolkit.legacyUserProfileCustomizations.stylesheets → true.