Rainbow flashes across entire screen on boot. Normal?

My Raspberry Pi2 running OSMC flashes a four section rainbow across the entire screen before boot. It’s on the screen for a couple seconds at most. I don’t appear to be having any issues (although I have lost my skin config a couple times after a reboot - I see there is a thread on this). My Pi3 running OSMC does not flash the rainbow squares. Is this normal behavior? I searched and only found info regarding being stuck on the rainbow screen.

It’s normal.

Thank you!