text: let toggle_status = null;
  const toggle_element = document.querySelector("#toggle #input");
  
  chrome.storage.local.get('toggle_status', (data) =>{
    toggle_status = data["toggle_status"];
    if ( (toggle_status===null) || (toggle_status=='false') ) {
      toggle_status = 'false';
      toggle_element.checked = "";
    }
    else {
      toggle_element.checked = toggle_status;
    }
  });
  
  document.addEventListener('DOMContentLoaded', function () {
      
      document.getElementById("checkbox").addEventListener('click', onclick_checkbox, false);
      document.getElementById("button_1").addEventListener('click', onclick_left, false);
      document.getElementById("button_2").addEventListener('click', onclick_right, false);
  
      function onclick_checkbox () {
        chrome.tabs.query({currentWindow: true, active: true}, 
          function (tabs) {
              url = tabs[0].url;
              url = url.match("https://www.overleaf.com/project/*");
              if (url !== null) {
                chrome.storage.local.get('toggle_status', (data) =>{
                  toggle_status = data["toggle_status"];
                  if (toggle_status == 'false') {
                    chrome.storage.local.set({"toggle_status": 'true'});
                    chrome.tabs.sendMessage(tabs[0].id, 'true');
                    chrome.browserAction.setIcon({path: '../icons/overleave-active.png'});
                  }
                  else {
                    chrome.storage.local.set({"toggle_status": 'false'});
                    chrome.tabs.sendMessage(tabs[0].id, 'false');
                    chrome.browserAction.setIcon({path: '../icons/icon-16x16.png'});
                  }
                });
              }
        })
      }
  
      function onclick_left () {
        chrome.tabs.query({currentWindow: true, active: true}, 
          function (tabs) {
              chrome.tabs.sendMessage(tabs[0].id, 'new_project');
        })
      }
  
      function onclick_right () {
        chrome.tabs.query({currentWindow: true, active: true}, 
          function (tabs) {
              chrome.tabs.sendMessage(tabs[0].id, 'projects');
        })
      }
    }, false)