Bug 42583: Modify moz-support-link for Tor Browser.

  #setHref() {

    let torManualPage = this.getAttribute("tor-manual-page");

    if (torManualPage) {

      const [page, anchor] = torManualPage.split("_", 2);

      let locale = Services.locale.appLocaleAsBCP47;

      if (locale === "ja-JP-macos") {

        // Convert quirk-locale to the locale used for tor project.

        locale = "ja";

      }

      let href = `https://tb-manual.torproject.org/${locale}/${page}/`;

      if (anchor) {

        href = `${href}#${anchor}`;

      }

      this.href = href;

      this.href = `about:manual#${torManualPage}`;

      return;

    }

    let supportPage = this.getAttribute("support-page") ?? "";

    // For tor-browser we sometimes want to override firefox support links with

    // our own.

    // See tor-browser#40899.

    switch (supportPage) {

      case "preferences":

        // Shown twice in preferences, both as `{ -brand-short-name } Support`.

        // Instead of directing to support for preferences, we link to general

        // tor browser support.

        // See tor-browser#32092.

        this.href = "https://support.torproject.org/tbb";

        return;

      // Fall through to support.mozilla.org

    }

    let base = MozSupportLink.SUPPORT_URL + supportPage;

    this.href = this.hasAttribute("utm-content")

      ? formatUTMParams(this.getAttribute("utm-content"), base)