displays not detected in ubuntu 22.10 kernel 5.9.0-23

[leonadato]

I've got a Dell Latitude 5521 running Ubuntu 22.10. It's connected to a Wavelink USB3 port replicator which is driving 2 external monitors via HDMI.

When I boot into the latest kernel (5.19.0-23), it cannot see the 2 external monitors.

BUT... when I boot into kernel 5.19.0-15, the 2 monitors are there no problem.

Per the instructions here (https://www.displaylink.org/forum/showthread.php?p=94453) I've
removed displaylink
rebooted
removed evdi 1.11
removed evdi 1.12
re-installed linux headers
re-installed displaylink
,

...and rebooted again just for good measure. No joy.

xrandr --listproviders says:

Providers: number : 1
Provider 0: id: 0x46 cap: 0x9, Source Output, Sink Offload crtcs: 4 outputs: 4 associated providers: 0 name:modesetting

[leonadato]

UPDATE:
I removed everything, re-installed, and now the displays are dark in both kernels.

Yay for consistency, I guess?

Still, I really REALLY would like to get my other monitors working.

[leonadato]

Welp, I went back into BIOS to double-check secure boot and sure enough it was on, and sure enough disabling it immediately allowed the external monitors to work.

So for future generations, here's a potential answer. Good luck!