Tantek Çelik wrote a post in 2015 called “js;dr = JavaScript required; Didn’t Read.”. It was about a fundamental problem regarding sites that depend on JavaScript for rendering content: Indexability. Although search engines got much much better at indexing JS, it still remains a major problem, which I learned the hard way a few weeks ago.
On October 30, Readability closed down its “read it later” bookmarking service. Although I had not been a regular user of the service, I had created a fair amount of lists of interesting links for the students of my Interface Prototyping seminar using a site called readlists.com, a service by Readability that depended on the Readability API – and JavaScript (require.js, to be exact).
Unfortunately, Readability went offline pretty quickly, giving all users only 30 days to export their personal data. Somehow, I must have missed the Medium article or an email that announced the shutdown. So I learned about it the hard way when I opened the site with my students. No lists. No links. Gone.
Not too big a problem, I thought. And a good opportunity to show the students the beauty of the Internet Archive! But when I went there to look at the snapshot of the site, I stared at this:

The Wayback Machine snapshot of Readlists only shows a spinning wheel.
I don't want to blame the people at Readability for shutting down their service. It is also totally their decision when and how fast to go offline. But one fact remains: Once again, many users irreversibly lost their data. And this was not only due to the fact that the site was shut down, but mainly because the content was dependent on JavaScript (and an API) in a way that made it invisible to the crawler of the Internet Archive – and by that dead to history.
After five years, all that remains of Readability is a spinning wheel in the Internet Archive and a Wikipedia article.
Or, as Tantek puts it:
“If it’s not curlable, it’s not on the web.”
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