Thanks, Belgarath. And it happened again today, after my last post. Not on sguforums, but same thing. Okay, so my hardware is getting too old for my software. Maybe in 2016 I'll have to get a new computer. It's kind of annoying, because the computer works fine and does what I need it to. If I could freeze all my software I'd probably get another decade of reliable use out of it. Except that I suppose all the web sites will continue to change until the old software can no longer render them.
BTW, as near as I can tell, web sites render just as fast as they did with hardware acceleration turned on. I wonder if my computer even has the hardware in question. It's about a decade old, and I think it was the first model of iMac to use a dual-core CPU.