This came as a surprise to me.
I remember trying to run Raspbian Jessie on a raspberry pi 4 and it simply didn't work, with all messages indicating that the kernel is different.
Because of that, I always have set my SD cards either for the pi3 or pi4. (more precisely, micro SD cards, of course)
Today I was checking contents of some unmarked SD cards, using a Pi4 and a Pi3
Inserted a card on the pi3 (B+) and it booted perfectly to the Bulllseye 32 desktop. I realized that it was an SD card I prepared for the Pi4, so I tested a group of cards with Buster 32, Bullseye 32 and Bookworm 32. All of them boot perfectly.
Based on that I did some web search and some say work, some say don't. Some say that they don't work if there are some special hardware configured, drivers and so.
Have not tested cards prepared on a Pi3 yet, but wanted to share this finding.
The sad part is that my AppGameKit game at full screen runs very slow on the Pi3B+. On landscape mode (no screen rotation), full screen, am getting between 7 and 14 FPS. Guess that in 90 degree rotation for a portrait monitor it will be half of that.
Let's go to Mars
