I have a nice custom image at bootup, but want the rainbow screen to go away...using latest stretch & rpi3.
I found these steps & repeated them EXACTLY & re-tried them 3 times...but during each boot the rainbow square (4 colors) keeps showing up...are these invalid edits? The display is a LCD plugged into the HDMI jack. I tried putting the suggestion at the bottom, then tried top of the config file, but still no luck.
1. Remove Rainbow Screen
1-1. Open “/boot/config.txt”.
sudo nano /boot/config.txt
Then add below at the end of the file.
# Disable rainbow image at boot
https://scribles.net/silent-boot-up-on- ... n-stretch/