Hi! Nice, what mirror glass did you used?

@keyun21 Ahhh, I see now. Your npm needs to be updated. Simply open a new terminal and type npm i -g npm and press your Enter key.

Found it. https://forum.magicmirror.builders/topic/9707/save-performance-when-rotating-screen-e-g-on-raspberry-pi Looks like this is a better option. Will give it a try myself.