[rlpb]

Or, alternatively, just git rebase -i, mark the comment for amending with "e", then when it stops for amending amend what you need and commit with "git commit --amend", then "git rebase --continue" to finish. Wrap with stash if you don't have a clean working directory to start with.

[Cthulhu_]

That's what I do right now, leading to temporary commits like "Squash me" followed by the kinda awkward interactive rebase flow, which is the only instance where I use Vim, and awkwardly and with some resistance at that.

[rlpb]

My method does not lead to any temporary commits.