More on Google’s Javascript Handling

Many of you probably noticed my recent post without any substantive content. I was seeking to answer the following questions…

• Does Google wait for timeouts and display that content in the index? is that content searchable?
• How does Google handle content generated at intervals in javascript?
• Will Google index content that is only displayed after an action like a button click occurs?

We now have some pretty solid answers to each question…

• Does Google wait for timeouts and display that content in the index? is that content searchable?
  Yes. Google does wait for timeouts and display that content in that index. That is to say, the content that was displayed after the timeout is included in the search index such that you can find it by searching Google for it. In this case, the phrase “test2x1content” can be found in Google when searched with quotes. This content is displayed only after a short 300ms delay.

  Interestingly, we discovered something else. If that delay uses javascript to modify existing content, both the previous and the new content are indexed and searchable in Google. In this case, two strange sentences “the marker blue wax among” and “elephant made candle popular kids” were stored in separate DIVs then joined together after 300ms, one word after the other, to create “the elephant marker made blue candle wax popular among kids”. You can find the test JS experiment with BOTH the original sentences and the joined sentences.

• How does Google handle content generated at intervals in javascript?
  This is interesting because it appears Google only uses the last state of the content. In this case, I set the test to count up every 300 milliseconds and on 2 different installations Google stopped at 66, or 19800ms (1 interval before 20 second mark). Google only indexed test66x1content and did not index any other previous states. It is possible that you could display content to a user with an interval set then have it switch just before the 20 second mark to what you want Google to see, then switch back right after. It is likely possible to do this at a speed which the user would not notice.
• Will Google index content that is only displayed after an action like a button click occurs?
  This is interesting because it indicates it may be possible to inject non-searchable content on the page with a simple full-page mouseover.

I am looking forward to doing a lot more tests on how Google handles far more complex Javascript. I want to see what kind of memory bounds Google might place on parsing Javascript as well.