Support for Logitech MX keyboard incomplete

[hepabolu]

Note:
Before bug reporting, please make sure you have tried the latest (alpha) version of BetterTouchTool and that you have already tried to restart your system :-). If you encounter a crash, please attach a crash log from the macOS Console.app's "Crash Reports" section.

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Describe the bug
I uninstalled LogitechOptions and installed the latest BTT beta (6.169) through Setapp.
I want to use all the BTT features for my keyboard, but I also want the function keys to behave as function keys, not as commands (e.g. volume up/down).

I have connected the keyboard using Bluetooth and set the configuration. See screenshot.

The configured special keys as defined here, do work, but the function keys do not work at all, not as function keys and not as command keys.

I would like to have the functionality that pressing F11 gives me the default setting of showing my desktop and fn + F11 the mute functionality.

I could of course try to create triggers for each function key, but I read somewhere that the fn+function key is not recognized by BTT, because it happens on device. So I cannot recreate the mute functionality.

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Affected input device (e.g. MacBook Trackpad, Magic Mouse/Trackpad, Touch Bar, etc.): Macbook + MX Keys keyboard

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Screenshots
If applicable, add screenshots to help explain your problem. (You can just paste or drag them here)

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Device information:

• Type of Mac: Macbook Pro M3
• macOS version: 15.7.3
• BetterTouchTool version: (please post the exact version - not just "the latest one") 6.169

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Additional information (e.g. crash logs, related issues, etc.):

[Andreas_Hegenberg]

BTT needs to override the standard functionality of the selected keys so you can remap them in btt. However the FN+ key action should continue to work (i.e. fn+ f9 should producs a standard f9 press). This seems to work fine with my mx keys, does it not for you?

[nutilius]

Does fn+esc doesn’t work for your keyboard?

[hepabolu]

Yes the fn+key gives me the respective function key (e.g. F11) and the ‘action’ (e.g. mute on F11) does not work. However, in macOS and previously in LogitechOptions I have/had set that pressing the F11 key works as function key and fn+F11 as mute key. So the reverse of how the MX keys work now. Which is now confusing because the built-in keyboard of my laptop still works as I have set it (fn+F11 = mute) while the MX-keys I need to press fn+F11 to get the F11 key.

Is there a setting to call in BTT to switch this for the MX keys?

I noticed in cpg-docs/hidpp20 at master · Logitech/cpg-docs · GitHub a setting named fn inversion, so that seems what I want.

[Andreas_Hegenberg]

v6.197 alpha adds support for the FN Key inversion - however I haven't tested it yet!

[hepabolu]

Thanks a lot! It will take a while before I am home again and be able to test it.

[iandol]

I couldn’t get it to work on my K380:

I got a request timeout when applying the settings and my FN keys are special function keys not F1-F12

[hepabolu]

How can I try this alpha version with a Setapp version of BTT?