text: chrome.runtime.onInstalled.addListener(() => {
    // do nothing.
  });
  
  /*
  chrome.tabs.onUpdated.addListener( function (tabId, changeInfo, tab) {
    if (changeInfo.status == 'complete') {
      let url = new URL(tab.url);
      let host = url.hostname;
  
      setTimeout(() => {
        chrome.storage.sync.get(host, (res) => {
          if (res[host] == true) {
            chrome.scripting.executeScript({
              target: { tabId: tabId },
              function: firstOpenATag,
            });
          }
        });
      }, 5000);
    }
  });
  
  function firstOpenATag() {
    var links = document.getElementsByTagName('a');
    for (var i=0, len=links.length; i < len; i++) {
      links[i].target = "_blank";
    }
  }
  */