I use Alchemy as my viewer. As of a few minutes ago it told me it couldn't auto-fill my name and password. Which I had set to saved.... So I did it myself. Then it told me it had trouble logging in and gave me the option to teleport home, which I did. And when I logged in all my settings were back to default. I have had to reset my toolbar and everything, including the custom colors I had saved in my edit color bar.
What happened? This has never occurred before and I've been on SL for years.