On Tue, Apr 08 2025, Rutherther via Bug reports for GNU Guix wrote:

>>> Okay, I was wrong. The problem is only when ICECAT_SYSTEM_DIR is unset.
>>> When it's set to anywhere, like /, it works fine for me as well.
>>
>> Great!
>>
>> Closing :)
>
> Should this really be closed? I think it's a bug that ought to be fixed.
> Or at least the user's should get to know somehow they have to set it.
> If user is not using any extensions via Guix, they won't be able to use
> native messaging unless they know about this culprit.

Oh right, I reopen.

Would the attached patch fix your issue?  (Can't test it right now.)

Thanks,
Clément