It would be amazing to be able to set the "FN" key to a different customized modifier key or shortcut.
I can't find a way to do this directly using the BTT alone, or without having to download other keyboard-shortcut apps like Karabinder Elements
I think adding this new key as an customizable shortcut could improve drastically the amount of shortcuts that you can assign, giving users an addicional modifier to add a new layer of quick-access shortcuts.
If that means you want to use fn as a modifier, you can do that with BTT.
Are you aware that BTT can distinguish between left and right modifiers, allowing you to set up different shortcuts? This doubles the number of possible shortcuts.
yeah, and are you aware that if you press the "FN" alone, BTT doesn't register it as a shortcut to customize?
Yep key sequences will work fine for this!
If you really need to remap it completely at system level you can also achieve that via the low level key remap: Low Level Key Remapping · GitBook
Key sequences will also be able to detect it if you remap it to nothing via the low level key remap - in case you don't want it to trigger FN anymore.
Mm, but what is the difference to other modifiers? If only one modifier is supposed to trigger something, it always needs a key sequence. This applies to fn, cmd, ... 
Yes, no difference - this applies to all modifiers.
I set it up but it doesn't trigger, my idea is to have an aditional modifier key, to be able to add an entire new layer of shortcuts to it. like using FN as a "right-shift" key
not sure what I might be missing
I probably don't understand what you mean... but fn is already a modifier with BTT. You can set up any shortcuts... fn + any letter. Isn't that what you want?
yep, as Frank mentioned this is supported by default in BTT‘s keyboard shortcuts. For this there is no need to remap anything, just record your shortcuts while holding FN.
When I press it with any key, BTT doesn't read it altogether
I use an MX Keys Mini keyboard, from Logitech
If I press "FN+L" only "L" appears on the panel.
ah, unfortunately on Logitech Keyboards the FN key by default is entirely handled in hardware as far as I know the OS doesn't even see it (or the logitech software blocks it from reaching other apps)
AFAIK this can be configured somewhere in the Logitech software, but unfortunately I don't know where. Can Karabiner Elements do this out of the box?
You are correct, this is a hardware thing. A logitech limitation on the keyboard itself.
I appreciate everyone who took time to give me a hand with this!
@tirettajose Even if you can't use fn, there are many options if you want more modifiers. For example:
- Try BTT hyperkey or
- You can double-tap and hold a modifier (key sequence) to block the keyboard. For left cmd it looks like this.
As long as you hold down cmd, you can use any letter for shortcuts. This means that cmd + A triggers something, and tapping cmd twice + A triggers something else.
Not sure if it's just me, but double tapping for any keyboard shortcut, like pressing "a" a couple times for a defined shortcut always crashes the app on my computer.
I have an M2 Max MBP chip