chrome.runtime.onMessage.addListener(
  function (rq) {
    if (rq.action === "content_func_1") {
      alert("content_func_1");
    }
  }
);


if (location_startsWith("www.instagram.com/")) {

  $("article img").attr("title", "hello");



}

// newTab();
// openTab("https://news.bbc.co.uk");
// updateTab("https://news.bbc.co.uk");

//alert("content");


function newTab() {
  chrome.runtime.sendMessage({ "action": "new_tab" });
}

function openTab(url) {
  chrome.runtime.sendMessage({ "action": "open_tab", "location": url });
}

function updateTab(url) {
  chrome.runtime.sendMessage({ "action": "update_tab", "location": url });
}


function location_startsWith(needle) {
  return startsWith(window.location.href, "http://" + needle) || startsWith(window.location.href, "https://" + needle);
}

function startsWith(haystack, needle) {
  return (haystack.toLowerCase().indexOf(needle.toLowerCase()) == 0);
}