brz cat-revision fails on git repositories

brz: ERROR: AttributeError: 'LocalGitRepository' object has no attribute 'revisions'

Traceback (most recent call last):
  File "/home/jelmer/src/breezy/integration/breezy/commands.py", line 1016, in exception_to_return_code
    return the_callable(*args, **kwargs)
  File "/home/jelmer/src/breezy/integration/breezy/commands.py", line 1202, in run_bzr
    ret = run(*run_argv)
  File "/home/jelmer/src/breezy/integration/breezy/commands.py", line 759, in run_argv_aliases
    return self.run(**all_cmd_args)
  File "/home/jelmer/src/breezy/integration/breezy/commands.py", line 784, in run
    return self._operation.run_simple(*args, **kwargs)
  File "/home/jelmer/src/breezy/integration/breezy/cleanup.py", line 137, in run_simple
    self.cleanups, self.func, *args, **kwargs)
  File "/home/jelmer/src/breezy/integration/breezy/cleanup.py", line 166, in _do_with_cleanups
    result = func(*args, **kwargs)
  File "/home/jelmer/src/breezy/integration/breezy/commands.py", line 1219, in ignore_pipe
    result = func(*args, **kwargs)
  File "/home/jelmer/src/breezy/integration/breezy/builtins.py", line 457, in run
    revisions = b.repository.revisions
AttributeError: 'LocalGitRepository' object has no attribute 'revisions'

brz 3.0a2 on python 2.7.15 (Linux-4.19.0-2-amd64-x86_64-with-debian-buster-
    sid)
arguments: ['/home/jelmer/src/breezy/integration/brz', 'cat-revision', '-r',
    '-1']
plugins: bash_completion[3.0a2], changelog_merge[3.0a2],
    commitfromnews[unknown], cvs[3.0a2], darcs[unknown], debian[2.8.6],
    email[unknown], fastimport[unknown], grep[3.0a2], launchpad[3.0a2],
    loggerhead[1.20.0], mtn[3.0a2], netrc_credential_store[3.0a2],
    news_merge[3.0a2], po_merge[3.0a2], propose[unknown], repodebug[unknown],
    stats[3.0a2], upload[3.0a2], weave_fmt[3.0a2]
encoding: 'utf-8', fsenc: 'UTF-8', lang: 'en_IE.UTF-8'

*** Bazaar has encountered an internal error. This probably indicates a
    bug in Bazaar. You can help us fix it by filing a bug report at
        https://bugs.launchpad.net/brz/+filebug
    including this traceback and a description of the problem.