Does a MarkdownPostProcessor render even relate to a particular EditorState?

How could a MarkdownPostProcessor get access to the document’s EditorState that it represents?

I would like to access some of my state (StateField) that is from the state that the source had when the markdown was generated. Since it is async, I don’t have a good way to know what state that would relate to.

Are these just so far apart (maybe Markdown stuff was all written before you even used CodeMirror?) that there is no relationship? For example, is the Reading view stuff just running off of the file’s text contents?