Process markdown in a worker

[eight04]

I got this message while trying to preview a 7MB markdown file.

[Cimbali]

Hmm 7MB might be a lot indeed. I didn't know workers were available for extensions, will definitely look into it.

[Cimbali]

Using workers is in fact really hard for this use-case, as the extension’s javascript files can not be loaded from the page where we inject the markdown rendering scripts, due to cross-site request limitations.

[eight04]

In my experience, it is possible to use worker in background page and extension pages but I'm not sure about content script.