Yeah it's funny that this specific glitch is specific to a certain era of iMacs/Safari. I mean, I get the theory that there is some voodoo combination of in-house loosey-goosey broswer-OS stuff that just so happened to birth this goofy, full-stop hang. But I dunno, vanilla web browsing to hard restart seemed out of the ordinary for mature OS X. In the beginning, I was sure it was memory. Or heat. There was a failing hard drive. But that guy gave me beach-balls. This one is too subtle.
And I thought however they accidentally invented it, they might accidentally un-invent it. I guess that's why people, or me, at least, are still subscribed to this thread.
And then as JesperA talked abt earlier, it seems not unlikely our backlights will fail before our Safaris don't. Look around, half the thread with an aftermarket boot SSD etc. Me too. I can edit video. (Sorta.) What a workhorse. So I can swallow switching to Chrome if I can keep this one going, and maybe I can even forgive their indifference to their backwards compatibility if they keep making em as good. And don't cut too many corners with the integrated app-OS cheats. Please don't sacrifice anything for fingerpaint function keys.