I have a subfolder latest Discourse installation (use official how-to).
I have a Gravatar account and Discourse used to load my picture with subdomain (default) installation.
But when I made a clean new subfolder installation, Discourse no longer loads my Gravatar picture (I keep using same email).
No matter how many times I keep pressing on update button next to Gravatar.
You can check that on my email there is a Gravatar picture actually.
When I try to upload an avatar picture the following happens:
Firstly, picture uploaded, and displayed
But than, after page reload, picture fall back to silhouette of gray fellow.
You can reproduce this behavior on this site