Invalid Website Protocol rule

meta {
    title: "Invalid Website Protocol";
    version: "1.2_2023-04-07";
    author: "CjMalone";
    link: "https://josm.openstreetmap.de/wiki/Rules/InvalidWebsiteProtocol";
    baselanguage: "en";
}

*[website!~/^https?:\/\/.*/], *[contact:website!~/^https?:\/\//] {
    throwWarning: "Websites should start with http:// or https://";
}

Rules_InvalidWebsiteProtocol.validator.mapcss, Rules_InvalidWebsiteProtocol.zip