old_contents: // Adds toggle for custom theme to Page Action.
  //
  // This file *only* controls that toggle, 
  // the logic behind enabling/disabling the theme is found in
  // core/js/customThemeHandler.js
  
  var customThemeToggle = (function(){
    var optionsLink = document.getElementById("options-link");
    var enableTheme = document.getElementById("enable-theme");
  
    chrome.storage.local.get("cmCustomThemeEnabled", function(response){
      var themeIsEnabled = !!response.cmCustomThemeEnabled;
      enableTheme.checked = themeIsEnabled;
      setEventListeners();
    });
  
    function setEventListeners() {
      optionsLink.addEventListener("click", function(){
        //http://stackoverflow.com/a/16130739
        var optionsUrl = chrome.extension.getURL('core/html/ces_options.html');
        chrome.tabs.query({url: optionsUrl}, function(tabs) {
          if (tabs.length) {
            chrome.tabs.update(tabs[0].id, {active: true});
          } else {
            chrome.tabs.create({url: optionsUrl});
          }
        });
      });
  
      enableTheme.addEventListener("click", function(){
        if (enableTheme.checked) {
          chrome.storage.local.set({"cmCustomThemeEnabled": true}, function(){
            sendToActiveTab({method:"enable-custom-theme"});
          })
        }
        else {
          chrome.storage.local.set({"cmCustomThemeEnabled": false}, function(){
            sendToActiveTab({method:"disable-custom-theme"});
          })
        }
      });
    }
  })();
new_contents: // Adds toggle for custom theme to Page Action.
  //
  // This file *only* controls that toggle, 
  // the logic behind enabling/disabling the theme is found in
  // core/js/customThemeHandler.js
  
  var customThemeToggle = (function(){
    var optionsLink = document.getElementById("options-link");
    var enableTheme = document.getElementById("enable-theme");
  
    chrome.storage.local.get("cmCustomThemeEnabled", function(response){
      var themeIsEnabled = !!response.cmCustomThemeEnabled;
      enableTheme.checked = themeIsEnabled;
      setEventListeners();
    });
  
    function setEventListeners() {
      optionsLink.addEventListener("click", function(e){
  
        // needed to prevent the click from propagating to the checkbox
        e.preventDefault();
        
        //http://stackoverflow.com/a/16130739
        var optionsUrl = chrome.extension.getURL('core/html/ces_options.html');
        chrome.tabs.query({url: optionsUrl}, function(tabs) {
          if (tabs.length) {
            chrome.tabs.update(tabs[0].id, {active: true});
          } else {
            chrome.tabs.create({url: optionsUrl});
          }
        });
      });
  
      enableTheme.addEventListener("click", function(){
        if (enableTheme.checked) {
          chrome.storage.local.set({"cmCustomThemeEnabled": true}, function(){
            sendToActiveTab({method:"enable-custom-theme"});
          })
        }
        else {
          chrome.storage.local.set({"cmCustomThemeEnabled": false}, function(){
            sendToActiveTab({method:"disable-custom-theme"});
          })
        }
      });
    }
  })();
subject: Add preventDefault on clicks on the 'edit' button next to the theme toggle in the page action popup. Without it, clicking edit actually toggles whether or not the theme is enabled which is incorrect.