Click-to-jump between rendered content and source, copy message source

[calischs]

Another enhancement for editing long posts is to imitate the feature in TexShop that allows a user to click on the rendered content and jump to the corresponding line in source. It seems the other direction would be nice to have as well.

According to Erik, as a bonus, implementing this feature would give a method to select rendered content and copy the corresponding source code. Useful for copy-pasting to other documents.

[edemaine]

Approach to this: write a Markdown plugin (after this) that emits a secondary data structure with the source <-> rendered mapping, character by character. Include this plugin only when needed (when editing, and when doing a copy operation, and when doing a r reply #539).

Here's a related plugin that does this at the paragraph level. Another plugin, perhaps better.

Synchronizing the scroll of side-by-side rendered content to the editor cursor would be a nice bonus of this.