As of today (I think), my identicon changed.
I've read Unexpectedly changing identicon, but that doesn't apply to me, since I didn't "change" from identicon to identicon, I didn't tinker with any settings.
What I don't get is that my e-mail address, hashed without any salt, gives d2e123006e6dfab0f1cadd8dda699cfd, as verified by
echo -n $email | md5sum. It looks like I should have had the new identicon for longer. But I didn't. I pulled the old one from the Google cache of my StackOverflow profile, just to make sure I wasn't going mad. The cached page is from Feb 19, just under a week ago, and features the old image.
So what happened? If the old identicon didn't come from my e-mail address, where did it come from? And why did it suddenly change to one that is based on my e-mail address?
The comments point out that the Android app displayed the old identicon for a bit longer than the sites, but that too now displays the new one.