If you've made a mistake within while working on your email/template in the email composer, click the 'undo' arrow at the top right of the page. This action will swiftly revert the last edit you made.
Alternatively, you can use the keyboard shortcut by holding down ctrl+z.
To reinstate any actions that you've undone, simply click the 'redo' arrow located next to the undo arrow.
This feature allows you to backtrack and forward-track through your editing history, providing you with flexibility and control over the changes made within the email composer.