They can do that with base Macs, but all peripheral hardware/software combinations including non Apple?? No. There are way too many for that, and the time required would be ridiculous.
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The fact that it occurred on one day on one particular site for many people, and without any software update on their Macs mysteriously disappeared the following day???
Yosemite isn't perfect, far from it. However this was a google issue. Youtube wasn't playing nice with safari.
You Apple apologists are really something. I am done with apple and this forum.