git-sim rebase --rebase-merges 185d138a --onto another-branch
usage: git-sim [-h] [--title TITLE] [--logo LOGO] [--outro-top-text OUTRO_TOP_TEXT] [--outro-bottom-text OUTRO_BOTTOM_TEXT] [--show-intro] [--show-outro] [--media-dir MEDIA_DIR] [--low-quality] [--light-mode]
               [--speed SPEED] [--animate] [--max-branches-per-commit MAX_BRANCHES_PER_COMMIT] [--max-tags-per-commit MAX_TAGS_PER_COMMIT] [-d] [-r] [--video-format VIDEO_FORMAT]
               {log,status,add,restore,commit,stash,branch,tag,reset,revert,merge,rebase,cherry-pick} ...
git-sim: error: unrecognized arguments: --rebase-merges --onto another-branch

$ git-sim rebase -h
usage: git-sim rebase [-h] branch

positional arguments:
  branch      The branch to simulate rebasing the checked-out commit onto

options:
  -h, --help  show this help message and exit