A recent update on Mac OS X (10.8.2+) removed the Java and required users to download/install new Java from Oracle’s site. This also came with a new problem: Chrome in Mac OS X will not be able to run Java applets because it is a 32 bit browser.
Well, not much we can do about that (unless you work at Google or Oracle). Therefore legacy sketches that run on Java will not be displayed to Chrome users and they will be requested to open the sketch in another browser.
This will come in the next code push to OpenProcessing. pff. I hate browser problems..