function copyUrl() {
  document.navigator.clipboard.writeText(tab.url).then(
    function () {
      console.log(`Copied URL: ${tab.url}`);
    },
    function (err) {
      console.error(`Something went wrong..`, err);
    },
  );
}

chrome.action.onClicked.addListener((tab) => {
  chrome.scripting.executeScript({
    target: { tabId: tab.id },
    func: copyUrl,
  });
});