By default when crontab-e is run for the first time, we get the choice to set the editor.
The selected editor is stored in a file ~/.selected_editor
However, if the selected editor needs to be changed later, the command is –
select-editor
To reset or unset the selected-editor completely, we can remove the ~/.selected_editor file completely.
Ref: https://www.howtogeek.com/410995/how-to-change-the-default-crontab-editor/