athena/unstable branch merges only from upstream emacs.git#master, and then is
only tagged and uploaded to athena after running locally for a day or so to
confirm that nothing obvious is broken.  Build with 'dgit sbuild -d CODENAME
to get something to test, and then use rebuild-for-athena to build, tag and
upload.

athena/CODENAME-bpo: backported from athena/unstable, automatically updated by
rebuild-for-athena when preparing the version of athena/unstable to upload to
athena as described above.

tmp/HOSTNAME: short-lived branch to test out patches/series not in upstream
master by running Emacs with those patches on my main laptop during regular
Emacs usage.  Not pushed anywhere.  When want to do this, create branch
starting from athena/unstable, merge/apply the series, dch, build and install
the .deb, restart Emacs.

To test running Emacs with patches/series not in upstream master without
affecting my regular environment -- typically because I want to do some
particular testing of them which takes just a few minutes -- make a temporary
branch based on upstream master (not athena/unstable), build, and run the copy
of the just-built in-tree copy of Emacs.

 -- Sean Whitton <spwhitton@spwhitton.name>, Tue,  2 Feb 2021 16:00:14 -0700