Getting the Option key working as Alt in macOS

[mrjones2014]

Kitty

Add the following configuration option to ~/.config/kitty/kitty.conf:

macos_option_as_alt both

Alacritty

Add the following key bindings to ~/.config/alacritty/alacritty.yml:

# for Alt+h/j/k/l
key_bindings:
  - { key: J, mods: Alt, chars: "\x1bj" }
  - { key: K, mods: Alt, chars: "\x1bk" }
  - { key: H, mods: Alt, chars: "\x1bh" }
  - { key: L, mods: Alt, chars: "\x1bl" }

iTerm2

Press ⌘+, to open preferences, go to the "Profiles" top tab,
then go to the "Keys" tab and change "Left Option key" and/or "Right Option key"
to "Esc+".