SOLUTION:
- Ctrl+U -> Ctrl+A -> Ctrl+C -> Notepad++ Ctrl+V to paste it there.
- Optional: Use the TextFX or Tidy Plugin to format the code quickly and maybe identify tags etc easier. But not necessary for Step 3:
- Use the HTML Tag Plugin in notepad++ via Shift+Ctrl+T to select a HTML Tag until its closing tag (including opening and closing tag), see --> Just copy the selection via Ctrl+C
https://superuser.com/questions/174599/notepad-jump-between-opening-and-closing-html-tags