rebase-helper fails to build with Sphinx 4.0.2 in Fedora 35 (currently Rawhide).

make -C docs clean man
make[1]: Entering directory '/builddir/build/BUILD/rebase-helper-0.24.0/docs'
rm -rf ../build/*
sphinx-build-3 -b custom-man -d ../build/doctrees   . ../build/man
Running Sphinx v4.0.2
loading translations [en]... done
making output directory... done
...
writing... rebase-helper.1 { } failed
Exception occurred:
  File "/usr/lib/python3.10/site-packages/docutils/nodes.py", line 625, in __getitem__
    return self.attributes[key]
KeyError: 'domain'
make[1]: Leaving directory '/builddir/build/BUILD/rebase-helper-0.24.0/docs'
make[1]: *** [Makefile:131: man] Error 2

For the logs from testing build attempts, see:
https://copr.fedorainfracloud.org/coprs/ksurma/pygments-2.9.0/package/rebase-helper/

You can test you package using Koji scratch build
koji build --scratch <srpm>

For details regarding the Sphinx change, see https://fedoraproject.org/wiki/Changes/Sphinx4
Let us know here if you have any questions. Thank you!