Is your feature request related to a problem? Please describe.

When there is a divergent change, one usually doesn't want to use the change id to refer to all of the commits. A recent Discord discussion had an example where one side of the divergence was not shown in the log output. In such cases, it's easy to think that e.g. jj abandon <change id> would just abandon the visible commit.

Describe the solution you'd like

If users rarely want to refer to all the sides of a divergent change, would could just make it an error. We can provide a revset function for when the user actually does want all sides of the divergence.

Describe alternatives you've considered

Keep the current behavior.