External display stopped working after upgrade to 5.18 on pinebook pro

After upgrade to 5.18 the external monitor connected to the pinebook pro stopped working. The monitor is connected through the pinephone usb-c dock. It worked perfectly fine until 5.17.x.

When connecting/disconnecting the usb-c dock, I don't see anything related to displays through either journalctl or dmesg. Until 5.17.x, there would be at least some messages, even if the monitor connection failed (which did occasionally happen). The other peripherals connected to the dock are still recognized and fully functional.

Nothing in my setup changed except for the kernel upgrade and the removal of the uart_arc kernel module from /etc/mkinitcpio.conf.