See the Pen Notepad by Captain Anonymous (@ethicist) on CodePen.
Минимальный вариант
<html contenteditable>
Версия без ошибок (https://validator.w3.org/nu/)
<!DOCTYPE html><html lang="en" contenteditable><head><title>Notepad</title></head></html>
See the Pen Notepad by Captain Anonymous (@ethicist) on CodePen.
<html contenteditable>
<!DOCTYPE html><html lang="en" contenteditable><head><title>Notepad</title></head></html>