const PAGE = "data:text/html,page";
async function test_on_browser(browser) {
  ok(!browser.audioMuted, "Audio should not be muted by default");
  browser.mute();
  ok(browser.audioMuted, "Audio should be muted now");
  await BrowserTestUtils.withNewTab(
    {
      gBrowser,
      url: PAGE,
    },
    test_on_browser2
  );
  browser.unmute();
  ok(!browser.audioMuted, "Audio should be unmuted now");
}
function test_on_browser2(browser) {
  ok(!browser.audioMuted, "Audio should not be muted by default");
}
add_task(async function () {
  await BrowserTestUtils.withNewTab(
    {
      gBrowser,
      url: PAGE,
    },
    test_on_browser
  );
});