I try with the youtube plugin. It works fine at my local machine, but it does not at Github Pages (official documentation).

Them I did it with some coffeescript.

  • At the markdown post, I added this small HTML snippet <div id="youtube_video_id" class="youtube"></div>.
  • At _includes/footer.html, which is called at my default layout. I put this line: <script src="/assets/js/youtube.js"></script>
  • And add this new file: assets/js/youtube.coffee
---
---

$ ->
  $('.youtube').each ->
    width = 560
    height = 420
    $(@).append "<iframe width=\"#{width}\" height=\"#{height}\" src=\"https://www.youtube.com/embed/#{@id}\" frameborder=\"0\" allowfullscreen></iframe>"

Some advices here: the file must start with 2 lines of ---. Since the file has extension .coffee, the script at src requires the same file with extension .js.