Safari for Yosemite and El Capitan should both continue receiving updates (minimally at least security updates) for the time being. I think the policy has been to support the two previous versions when a new one comes out.
Out of curiosity, do you have Flash enabled in your browsers? Other plugins?
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The opposite of a fact is falsehood, but the opposite of one profound truth may very well be another profound truth. - Niels Bohr
