Registering space as an execution key, requires a literal to be typed

[patrickberkeley]

It's weird to have the executionKey be whitespace:

keyManager.addMacro({
            executionKey: ' ', // <- weirdness
            keyEvent: 'keydown',
            callback: () => {
                console.log('spacebar');
            }
        })

[jordpo]

This would make more sense as space.