Can I undo changes in a PDF editor?
Yes. PDF by Zaweba gives every change a named undo step on Ctrl+Z, redo on Ctrl+Y, and Revert to saved to go back to the file as it was opened.
Yes. In PDF by Zaweba every change you make is one named undo step, so Ctrl+Z takes back the last thing you did and the menu tells you what it was, for example Undo Change text. Ctrl+Y redoes it. And if you want to throw away everything since you opened the file, Revert to saved takes you back in one go, and can itself be undone.
It's a reasonable thing to ask. Some PDF tools apply changes straight to the file, and others only let you undo a little. Knowing you can try something and take it back makes editing far less nerve-racking.
Named steps
Each change is recorded as a single step with a name. Moving a page, adding a bookmark, changing a word: each is one step. The name means you can see what Ctrl+Z will undo before you press it, which is much safer than undoing blindly and hoping.
Text editing keeps up to 30 steps of its own, so a run of small changes to wording can be stepped back through comfortably.
Revert to saved
Sometimes you want to start again. Revert to saved returns the document to how it was when you opened it, or when you last saved it. Unlike closing and reopening, it's a step you can undo, so if you revert and then realise one of those changes was worth keeping, Ctrl+Z brings the lot back.
Undoing as you work
Make your changes as usual. If something goes wrong, press Ctrl+Z, checking the name of the step in the Edit menu if you're not sure what it'll take back. Press it again to go further back, or Ctrl+Y to go forward.
To abandon everything since the last save, choose Revert to saved. To keep what you've done, save with Ctrl+S.
After saving, and after accidents
Undo covers the session you're in. A few other features help beyond that.
Autosave copies documents with unsaved changes to a recovery folder every 60 seconds, and after a crash the app offers to recover them at the next start. It's there for power cuts and the like.
File > Earlier versions opens each incremental save in a PDF in a tab of its own, so an older state of the file may still be there to see even after saving.
And when another program changes the file you have open, the app can reload it, asking first if you have unsaved changes, and Undo goes back if the reload wasn't what you wanted.
Habits that keep work safe
Save at natural points. Undo protects you within a session, but saving gives you a fixed point to revert to.
Keep the original. For important documents, save your edited version under a new name, so the original stays untouched however many changes you make.
Be careful with irreversible jobs. Redaction is meant to remove content for good, and Actions run on many files save their results. Test those on copies first.
So yes, you can undo in PDF by Zaweba, step by named step, and you can go back to the saved file whenever you want a clean start.
