Please stop using SlideShare

2014-11-30

Mike Gerwitz

There are many great presentations out there—many that I enjoy reading, or that I would enjoy to read. Unfortunately, many of them are hosted on SlideShare, which requires me to download proprietary JavaScript.

JavaScript programs require the same freedoms as any other software. While SlideShare does (sometimes/always?) provide a transcript in plain text—which is viewable without JavaScript—this is void of the important and sometimes semantic formatting/images that presenters put much time into; you know: the actual presentation bits. (I’m a fan of plain-text presentations, but they each have their own design elements).

There are ways around this. SlideShare’s interactive UI appears to simply be an image viewer, so it is possible to display all sides using a fairly simple hack:

Array.prototype.slice.call(
  document.getElementsByClassName( 'slide' ) )
    .forEach( function( slide ) {
      slide.classList.add( 'show' );

      var img = slide.getElementsByClassName( 'slide_image' )[0];
      img.src = img.dataset.full;
    } );

This will display all slides inline. But there’s a clear problem with this: how is the non-JS-programmer supposed to know that? Even JavaScript programmers have to research the issue in order to come up with a solution.

But ideally, I’d like to download the presentation PDF. SlideShare does offer a download link, but not only does it not work with JavaScript disabled, but it requires that the user create an account. This is no good, as it can be used to track users or discover identities by analyzing viewing habits. This would allow de-anonymizing users, even if they have taken measures to remain anonymous.

(By the way: at the time that I wrote this post, the EFF’s Surveillance Self-Defense Guide is LibreJS compatible and the JavaScript code that it runs is mostly free.)

I encourage presenters (and authors in general) to release the slides in an unencumbered document format, like PDF, HTML, OpenDocument, or plain text. Those formats should be hosted on their own website, or websites that allow downloading those files without having to execute proprietary JavaScript, and without having to log in. If those authors must use SlideShare for whatever reason, then they should clearly provide a link to that free document format somewhere that users can access without having to execute SlideShare’s proprietary JavaScript, such as on the first slide. (The description is iffy, since it is truncated and requires JavaScript to expand.)