**TL;DR:**
----------
As of this writing, the lxpanel Updater applet somehow only updates the kernel modules without changing the system release. I want to know why, and point out that `apt` resolves issues.
## Backstory: ##
Today, I installed the following updates using the Updater applet in the `lxpanel` menubar on RPi OS:

```
apt list --installed | grep 202208

linux-libc-dev/stable,now 1:1.20220811-1 arm64 [installed,automatic]
raspberrypi-bootloader/stable,now 1:1.20220811-1 arm64 [installed]
raspberrypi-kernel/stable,now 1:1.20220811-1 arm64 [installed]
```

After rebooting following the prompt, I noticed the following symptoms:  

 1. My second monitor is stuck on the rainbow startup screen. Replugging it and checking `xrandr` show that it's not detected.

 2. None of the daemons started by kernel modules were running.

After `Ctrl+Alt+F1`ing into tty1, I see at the top:  
```
[    3.003542] systemd[1]: Failed to start Load Kernel Modules.  
[FAILED] Failed to start Load Kernel Modules.
```
with the rest of the normal login screen below that, indicating that I successfully booted using Kernel 5.15.32-v8+

`systemctl status systemd-modules-load.service -l` shows:
```
● systemd-modules-load.service - Load Kernel Modules
     Loaded: loaded (/lib/systemd/system/systemd-modules-load.service; static)
     Active: failed (Result: exit-code) since Mon 2022-08-15 16:11:02 PDT; 2h 13min ago
       Docs: man:systemd-modules-load.service(8)
             man:modules-load.d(5)
    Process: 234 ExecStart=/lib/systemd/systemd-modules-load (code=exited, status=1/FAILURE)
   Main PID: 234 (code=exited, status=1/FAILURE)
        CPU: 37ms

Aug 15 16:11:02 raspberrypi systemd[1]: Starting Load Kernel Modules...
Aug 15 16:11:02 raspberrypi systemd-modules-load[234]: Failed to look up module alias 'lp': Function not implemented
Aug 15 16:11:02 raspberrypi systemd-modules-load[234]: Failed to look up module alias 'ppdev': Function not implemented
Aug 15 16:11:02 raspberrypi systemd-modules-load[234]: Failed to look up module alias 'parport_pc': Function not implemented
Aug 15 16:11:02 raspberrypi systemd-modules-load[234]: Failed to look up module alias 'i2c-dev': Function not implemented
Aug 15 16:11:02 raspberrypi systemd[1]: systemd-modules-load.service: Main process exited, code=exited, status=1/FAILURE
Aug 15 16:11:02 raspberrypi systemd[1]: systemd-modules-load.service: Failed with result 'exit-code'.
Aug 15 16:11:02 raspberrypi systemd[1]: Failed to start Load Kernel Modules.
```

Update
------
I searched for the missing modules and found they are unrelated and specified in `/etc/modules-load.d`. I also realized the recently updated kernel modules were version **5.15.56**, while the system was still at the previous version I mentioned earlier. Based on [this question][1], I reinstalled the kernel updates using `apt-get` (rather than the lxpanel updater) and rebooted, resolving the problems. [This RPi forum thread][2] demonstrates the same procedure with `apt`, which is more current.

Takeaway
========
As mentioned earlier, the lxpanel Updater applet somehow only updates the kernel modules without changing the system release.  
**Why is this? Should I be using `apt` instead of the Updater applet for kernel updates?**

  [1]: https://raspberrypi.stackexchange.com/questions/83329/linux-modules-mismatch-version
  [2]: https://forums.raspberrypi.com/viewtopic.php?t=289999