**TODO:** - [x] Solve missing imports - [x] Map to GFM (e.g. to get the proper map support) - [ ] Internal links (generate dummy ids/span) - [x] Typography : "--" - [ ] Color backgrounds ? (Not sure it's possible; not unless we convert the whole block to HTML?) - [ ] Need to normalize the size of images and drop the special attributes that are not rendered (?) - [x] Support for videos. - [ ] Can't split code in multiple cells once `figure()` appears