Users can use ⌘ + Z to undo the previous edit they made to the Workflow canvas. And use Shift + ⌘ + Z to redo the action.
For example undo...
  • User adds step, ⌘ + Z would delete the step
  • User adds section, ⌘ + Z would delete the section
  • User deletes a step, ⌘ + Z would bring it back
  • User deletes s section, ⌘ + Z would bring it back
Shift + ⌘ + Z would redo the actions listed above when they are undone.
If you have questions about this feature, post them below!