Twitter and Content-sensitive Filtering

Originally I intentend to give this post the title “Twitter and Censorship” but then I decided to rename it since censorship is a very hard word. Of course, censorship and filtering are related to each other. But read on about my discovery.

At first, I thought it is some kind of network failure, server overload, Javascript or Firefox bug. Twitter responded with “Tweet successfully sent!” but it simply did not appear.

Although the tweet counter increased,1 the tweet was neither in my main list nor in my tweets list. Tweets from others still continued to come in and I was also able to tweet and RT other messages.

Intuitively, this attracted my attention ­čśł

I tried to send my message again using a different language (originally it was German, now I tried in English) and the same happened: it simply was lost somewhere!

Here’s is the mysterious text I tried to tweet, in German and in English:

  • “M$ wird es nie schaffen, dass ein Word- oder Powerpoint-Doc auf jedem Computer gleich ausschaut.”
  • “M$ will never be able to make Word or PP docs looking equal on every computer.”

A friend of me tested this with his account to prove this behavior: same result. We changed the word “M$” to “MS” and then suddenly it worked: the tweet publicly appeared. After some further tests it turned out that not the Dollar sign is the reason for the filtering because the following tweet works fine:

  • “I’d like to say something about M$…”

The conclusion is that “M$” seems to be some kind of trigger which leads to some further tweet analysis which then decides if a tweet is accepted or not.

Strange things seem to happen behind the scenes…

  1. The local tweet counter seems to be maintained locally by Javascript. After a force-reload it dropped to the original value again.