Enter the following into your browsers URL bar:
data:text/html, <html contenteditable>
Want to style it? Go ahead!
data:text/html, <html style='background:#111;color:#DDD;font-size:x-large;' contenteditable>
You can print as PDF or copy the content when you're done. Unfortunately saving otherwise doesn't work out of the box. (tested in Chrome under Linux)
If that's not minimal I don't know what is ;)