patreon -> kemono

unpatreon.js

function unpatreon() {
    const KEMONO_DOMAIN = "https://kemono.su";
    const url = new URL(window.location);

    if (!url.hostname.includes("patreon.com")) {
        alert("This scriptlet only works on patreon.com");
        return;
    }

    // get id from URL path
    // /posts/xxxx-yyyy-12345
    const path = url.pathname.split("/");
    const slugs = path[path.length - 1].split("-");
    const id = slugs[slugs.length - 1];

    if (isNaN(parseInt(id))) {
        alert("Unable to get post id from URL");
        return;
    }

    // open new tab with link to kemono.su
    const kemonoUrl = `${KEMONO_DOMAIN}/patreon/post/${id}`;
    window.open(kemonoUrl, "_blank", "noopener noreferrer");
}
unpatreon();