Elegoo R-Pi 3.5" TFT Touch Screen on RPI 3?

Hi all,

Has anyone managed to get the Elegoo R-Pi 3.5" TFT Touch Screen to work on a Ubuntu Mate RPI 3 B+?

When I follow the instructions, I get an error on the first line:

ubuntu@ubuntu:~$ sudo apt-get install --reinstall raspberrypi-bootloader
Reading package lists... Done
Building dependency tree       
Reading state information... Done
E: Unable to locate package raspberrypi-bootloader
ubuntu@ubuntu:~$ 

I assume the instructions are for Raspbian. What's the equivalent command in Ubuntu?

Many thanks,
Christoph