hi,
quoting the (updated) 
https://tails.boum.org/contribute/git/ page:
  experimental
  ------------
  Generally, it's devel plus a few topic branches merged in.
  These topic branches are not ready enough to be merged into devel,
  but we seriously would like to get them fit for the next stable
  release, so this branch serves to test all these new features and
  bugfixes by building / getting a single image. The history of this
  branch is frequently rewritten and must no be used as the basis of
  any development.
  Please note that the experimental branch can be broken, have awful
  security problems and so on. No guarantee, blablabla.
I'll go on maintaining it as much, and as little, as I've been doing
privately until now. You're welcome to join the game. Especially the
"reset --hard devel + merge a bunch of topic branches in" dance is fun.
Note that you want to read git-rerere(1) - else it hurts.
cheers,
-- 
  intrigeri <intrigeri@???>
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