Processing.js sketch flickering when downloaded from OpenProcessing

Question

I tried downloading this sketch: http://www.openprocessing.org/sketch/11100 However when I run it on my version of Processing V2.1.2 in JavaScript mode it starts to have horrible flickering. As if there are two instances of the code running on top of each other.

When run off the website, the sketch runs perfectly.

What is different about what I am doing and what can I change to stop the flickering?

I have tried creating my own sketch and a similar problem is occurring.

My sketch and code is here: http://www.openprocessing.org/sketch/147128

Answer 1

I figured this out. I had multiple versions of processing.js in root and web-export folders. I don't know why this caused the flickering, but deleting all the files and letting Processing create its own file made it work