Undo - Split - selection

Can I have the option

  • documents
  • split
  • on selection

also undo on some pages?
How do I do that?

Thank you for your time and attention.

Ctrl+Shift+K, I’d say.
Ctrl+Shift+M, to Merge again.

For more Advanced Options, check out File > Import > Import and Split.

Yes, the Merge command is effectively the undo for splitting (and vice versa, though merging can be more work to untangle depending on how much of the inspector features you use).

It is not possible to undo either of these given how they work internally, and given the limitations of how undo is designed primarily as a text editing tool rather than something that can revert anything one might do—particularly in cases, like merge and split, where the result of the action might be to delete hundreds of actual files on your disk to make one single file from them, or the inverse.