jetpack_upload_handler_can_upload

    hook (filter): Optionally block uploads processed through Jetpack's upload_handler().<p>The filter may return false or WP_Error to block this particular upload.</p>

    Source: class.jetpack.php:3927

    jetpack_google_fonts_list

    hook (filter): Curated list of Google Fonts.

    Related to Modules:
    Source: modules/google-fonts.php:74