Visiting https://www.shadertoy.com/view/4tBGzc triggers Safari to reload a couple of times with the message "a problem was encountered on this page and it was reloaded", this is followed by a spinning beechball of death for about 30 seconds and the whole machine is unresponsive and then safari crashes.
Chrome ticket: https://code.google.com/p/chromium/issues/detail?id=486636
FF ticket: https://bugzilla.mozilla.org/show_bug.cgi?id=1163502
OSX: 10.10.2 (14C109)
Model: MacBook Pro (15-inch, Late 2011)
Processor: 2.2 GHz Intel Core i7
Ram: 4 GB 1333 MHz DDR3
Integrated GPU: Intel HD Graphics 3000 384 MB
Discrete GPU: AMD Radeon HD 6750M
Could you please attach a crash log?
Created attachment 252944 [details]
Created attachment 252945 [details]
Created attachment 252946 [details]