interesting, I used a different commit id today and it works.
However if I use the instructions on the page to get the right commit
it doesn't.
Ie if I use git rev-parse $TAG I get a commit id which will not work
when substituted above. Intead if I do git log -1 $TAG and use the
commit id of the tagged commit it works.
I wonder if the instructions have always been wrong or if they change
something subtler in github and now only the tag ids do not work
anymore ...