does #WriteFreely also support the open avatar service #Libravatar ? See https://www.libravatar.org/

Libravatar is primarly a specification of a DNS based mechanism to retrieve your preference as to which server should be used to fetch your avatar (based on email address or openid URL). I only mentioned it because by contrary "gravatar" itself is a centralized service and cannot possibly be controlled by others, thus making the verification less interesting, other than trusting gravatar owner more than the owner of the Fediverse instance you are using