Some of you may have noticed a 'bullseye' repository in raspberrypi.org
site. Bullseye is the code name for the next 'stable' Debian release.
This got me to wondering if I could do an in place upgrade to 'bullseye'.
So, yesterday I started with a virgin microSD card, copied the 'lite'
version of raspberry pi os to it; did update/upgrade; and then changed
the sources.list file to point at 'bullseye' instead of 'buster'. I then
did the update/upgrade and found that it worked quite well. I did have to
download two .deb files from the Debian armhf repos to solve a dependency
issue and then finished. It seems to have worked fine.

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