The ctrl Z function, that reverts the last action, does not work correctly. It can remove the last thing added, but cannot bring back the last thing deleted. It always does this. If this is how ctrl z is supposed to work in the text editor, please tell me so can I vote for it as a feature.
Wrrite in an article text editor. Delete some text. press ctrl Z. Nothing happens when it should bring back the deleted text.
This is a limitation of the plato editor. That editor will be replaced in the future. CTRL+Z works as expected in the Euclid (recommended) editor.