The Wayback Machine - https://web.archive.org/web/20190723074404/https://developer.jetpack.com/module/gravatar-hovercards/

    Browsing hooks for feature: Gravatar Hovercards

    grofiles_hovercards_data_callbacks

    hook (filter): Filter the Gravatar Hovercard PHP callbacks.

    Related to Modules:
    Source: modules/gravatar-hovercards.php:279