Undo and redo
Toolbar Undo / Redo, or Ctrl+Z / Ctrl+Y. Works for paint, fill, erase, Replace all, and more. See shortcuts.
Step back to a known-good state instead of clearing after small mistakes.
Vs clear canvas
Clear canvas asks for confirmation, then wipes everything. It is not a single-step undo. Prefer Undo whenever possible; clear only when you truly want a blank board.
Scope and habits
Paint, erase, fill, and replace-all usually join the undo stack. Redo works after undo until you draw again. Click the canvas if focus is in a dialog. Export PNG/CSV at milestones as backups outside the stack — see PNG and CSV.
Recommended habits
- Before large replace-all, confirm the foreground color; undo immediately on mistakes.
- Do not use clear canvas instead of multi-step undo.
- Export periodically on long sessions.
Export checkpoints
Export after major edits, proof before print, and save periodically. See PNG and CSV and shortcuts.