You can see the raw data for your profile here: reveals the following: changed on the settings page - not only next to the "upload new picture" button, but also in the topbar.
Nowhere else on the site except on the settings page is the topbar image changed.
And Firefox held onto it for several days, until I did a Ctrl F5 refresh.
(Not sure how long it would have kept it without Ctrl F5 refresh.)I've never set up a Gravatar account (if only for the privacy issues mentioned at meta.stackexchange.com/questions/4553/non-gravatar-avatar/…
The only way I've gotten Chrome to update Gravatars is by clearing my cache.
This could be resolved if Gravatar would send a proper Last-Modified header. (Note: that page is technically for reporting abuse, but it is the only way I could find to send a message to an actual person.
It would be very easy to add a version field to the users table and append it to the Gravatar query string, like this: Part of the problem is that Gravatar is sending a bad Last-Modified header.
Gravatar is sending a bad Last-Modified header, which makes the image stick around much longer than five minutes.
This makes Chrome, in particular, think that the image has not changed, even on a Ctrl F5 refresh.
Even though Gravatar sends a max-age of 300 seconds (5 minutes), the browser sees that Last-Modified hasn't changed and figures it doesn't need to re-download the file.
Very bizarre that only the settings page uses a different image.
Ah I see what must be happening, github isn't using robust cache busting techniques, so it probably takes howeverlong the CDN holds onto files for the image to update.