The default keymap for KBD66
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This is a fairly universal layout that supports standard ANSI, split backspace,
split left shift, and split right shift.
Cycle backlight: Fn + .
Backlight breathing: Fn + ,
Volume Up/Down: Fn + [ and Fn + ]
Mute: Fn + \
Sleep: Fn + /
Bootloader Mode: Fn + CapsLock