I just upgraded one volume to Yosemite. Using Safari 8.0.5, I went to a page on my site that has a hype animation. I can hear the intro music to the animation but the page is totally blank - not just the animation. No menu or header art, nothing. Same thing with Firefox.
The older Hype banner animation at the top of the home page plays okay, as does the small looping “dog” animation on the home page that is linked to the page in question.
I’ve had this animation up for around nine months without problems. I’ve made no changes to the animation or to the page. I assume that this is Apple’s doing.
Is there anything I can to to force the page to display?