Tested along with updated fedora-logos and f26-backgrounds packages, and a fresh user account, looks good here.
This message still appears for me, and the shell extension doesn't function when I try to turn it on:
org.freedesktop.DBus.Error.Spawn.ChildExited: Process org.fedoraproject.fedmsg.notify exited with status 1
Picasa (Google Photos) and Flickr publishing worked for me. Facebook publishing did not. This seems to be https://bugzilla.redhat.com/show_bug.cgi?id=1224562 -- which ironically could be addressed if upstream had these TLS verification fixes.