Make dev-template a live document

Would it be possible to make the /dev-template page a live editable page that would save things you typed into it?

I often make templates and like to hold onto them for future reference.

Another use case is troubleshooting when I need to move from screen to screen to find what I am looking for inorder to build a new template.

I think a simple save button that would write it all you a file and load that file when you load the page?