“Quick Scoop: In Jujutsu (`jj`), the command for duplicating a revision is `jj duplicate`. You can duplicate the current revision with `jj duplicate`, or a specific one with `jj duplicate [revision]`. The duplicated commits keep the same content but get new change IDs, which is useful for making a variation or preserving a state before edits.”[9][10]

What it means

If by “past 8” you mean a revision/commit in jj, the built-in way to duplicate it is jj duplicate. You can also place the duplicate before or after another revision using options like --insert-after or --insert- before.

Useful examples

  • Duplicate the current revision: jj duplicate
  • Duplicate a specific revision: jj duplicate <revision>
  • Insert the duplicate after another revision: jj duplicate --insert-after <revision>

If you meant something else

If “jjs” means a different app or game, the steps are likely different. The only verified “jj” result here is the Jujutsu command-line tool, where duplication is done with jj duplicate.

TL;DR: use jj duplicate for a revision copy in Jujutsu.