[remram]

But you don't know in advance whether a given version has the bug, that's kind of the reason for bisecting. Or do you mean you have 3 versions side-by-side: the last-known-bad, last-known-good, next-unknown-to-test?

FYI git has "worktrees": https://git-scm.com/docs/git-worktree

[Zambyte]

I mean making two workspace, and iteratively walking them towards each other in the revision tree, until to you cross the revision that introduced the bug (either both instances show the bug or neither does). There isn't really a reason to have three workspaces. If you want to mark where you were so you don't forget, you can just use bookmarks, but really you can just look at the operation log to see where you were.