Fn and Hyper

Two modifiers worth knowing before you pick hotkeys. Fn (the Globe key) works in a hotkey, and Hyper is all four modifiers at once.

Two modifiers are worth knowing before you pick hotkeys.

Fn (the Globe key on newer keyboards) works as a modifier in a hotkey, so fn+cmd+t is a valid combination. The engine never swallows Fn on its own.
Hyper means ⌘ ⌃ ⌥ ⇧ held together. Almost no other app uses it, so your own shortcuts rarely collide. In a key spec you write hyper+v.

⌃⌥⇧⌘V

hyper+v

The Globe key #

If pressing the Globe key opens the emoji picker or dictation, set Press 🌐 key to to Do Nothing in System Settings > Keyboard, so it can serve as a modifier.

A Hyper key of your own #

Switchboard can make Caps Lock your Hyper key (Library ▸ Remaps, or see Coming from Karabiner-Elements). Without that, press the four modifiers together.

See Keyboard shortcuts for the full key spec syntax.