After flashing the latest image, connect to it using serial console in the same way as previously, and log in as root.

Copy the librem5-evk-hdmi.dtb file to the correct place:

root@pureos:~# cp /usr/lib/linux-image-`uname -r`/freescale/librem5-evk-hdmi.dtb /etc/flash-kernel/dtbs/librem5-evk.dtb

Run the flash-kernel tool to install the new dtb file:

root@pureos:~# flash-kernel

Note: The LCD panel is disabled when using this dtb file.

Connect the HDMI monitor and reboot the system:

root@pureos:~# reboot

After the system exits U-Boot, a row of penguins will appear in the top-left corner of the monitor. Afterwards, Phosh will occupy the display, showing a login screen on a gray background.