I recently installed Debian 11 (bullseye) onto a second SSD in my computer (so I'm dual-booting with Windows on another). I used the official installation image and had to include the firmware-iwlwifi package on the installation drive which worked fine and was able to use my wifi adapter during installation.
Since then, when I boot into Debian and check the GNOME settings dialog I see "No Wi-Fi Adapter Found". However, this is inconsistent and it's sometimes working fine (I've yet to notice any pattern behind this).
I've discovered that my wifi adapter is an "Intel Wi-Fi 6 AX200 160MHz" and you can see in the snippet of output from
lspci -v here it is listed along with the iwlwifi firmware:
04:00.0 Network controller: Intel Corporation Wi-Fi 6 AX200 (rev 1a) Subsystem: Intel Corporation Wi-Fi 6 AX200 Kernel modules: iwlwifi
I can also see that the module is currently loaded, as per this snippet of output from
lsmod (note that third column is showing it is used by 0 running programs):
iwlwifi 294912 0
I've done some searching around and all previous questions I could find related to this (such as this one) are for an older Linux kernel or older versions of Debian (suggesting to use the backported package). However, as I understand it, my adapter should be supported by the latest version of package-iwlwifi for bullseye which I have installed.
What might cause this behaviour or what steps might I take to find and resolve the problem?