title: CodeMirror - what is addWidget for and how to use it?
body: <p>I want to make some extensions to CodeMirror.  The addWidget method seems like a promising starting point. The documentation states</p>
  
  <blockquote>
    <p>addWidget(pos, node, scrollIntoView) Puts node, which should be an
    absolutely positioned DOM node, into the editor, positioned right
    below the given {line, ch} position. When scrollIntoView is true, the
    editor will ensure that the entire node is visible (if possible). To
    remove the widget again, simply use DOM methods (move it somewhere
    else, or call removeChild on its parent).</p>
  </blockquote>
  
  <p>I don't really understand what that means or what I would use it for.  I cannot find a usage of it in the CodeMirror codebase nor anywhere else in google.</p>