Easy to use, Saving/Editing a bit quirky

Review title sums it up. Used this plugin instead of creating a child theme or custom plugin with modded email templates, so non-technical site owner can do their own edits to the templates in the future.

Just remember to click the publish button again every time you open a template in the editor before exiting the editor u/i, or your template gets reset to default (as of version 1.2.6 of this plugin.)