Sample AutoReload Extension (background.js)

//Related to http://stackoverflow.com/questions/15479683/all-chrome-tabs-present-the-same-error

var tabsToReload = [],interval; //TabsToReload holds the ids of the tabs
chrome.contextMenus.create({type:"checkbox",id:"reloadEntry",title:"Reload every 2 Minutes"}) //Add an Checkbox ContextMenu Entry with type "checkbox" to toggle reloading

chrome.contextMenus.onClicked.addListener(function(info,tab) { //Add An Click EventListener
    if(info.menuItemId == "reloadEntry" && info.wasChecked != info.checked) { //If the Menu Item which was clicked is the reloadEntry either remove or add the tab
        info.checked ? addTab(tab.id) : removeTab(tab.id);
    }
});

chrome.tabs.onActivated.addListener(function(info) { //Add a Listener when another Tab gets the focus
    var checked = !~tabsToReload.indexOf(info.tabId)
    chrome.contextMenus.update("reloadEntry", {title:"Reload Tab Every 2 Minutes",type:"checkbox",checked:false}) //Update the menu entry to represent the AutoReload state
});


chrome.tabs.onRemoved.addListener(function(tabId) { //Listen if a tab gets closed and call the removeTab functionb
    removeTab(tabId);
});


function addTab (tabId) { //adds a Tab to the ReloadList
    var index = tabsToReload.indexOf(tabId); //gets the indexOf of the tabId in the toReload Array
    if (!~index) { //uses a Bitwise NOT and a Logical NOT to get a boolean value, representing if the Tab is in the list
        console.log("Added Tab " + tabId);
        tabsToReload.push(tabId)
        if (tabsToReload.length === 1) { //If there weren't any tabs before, start the Interval
            reloadTabs();
            interval = window.setInterval(reloadTabs,120000);
        }

    }
}

function removeTab (tabId) { //Removes a tab from the List
    var index = tabsToReload.indexOf(tabId);
    if (!!~index) { //see above
        tabsToReload.splice(index,1); //splioes the tabs id of the array
        if (tabsToReload.length === 0) { //If no more tabs are left
            window.clearInterval(interval); //clear the interval
        }
        console.log("Removed Tab " + tabId);
    }
}

function reloadTabs() {
    console.log("Reloading tabs " + tabsToReload);
    for (var i = 0,j;j = tabsToReload[i];i++) { //iterate over the list of tabs
        (function (j) { //use a closure to capture j
            chrome.tabs.get(j, function (tab) { //get the tab
                tab ? chrome.tabs.reload(j) : removeTab(j); //if the tab exists reload it , otherwise remove it from the list (shouldn't happen)
            })
        })(j);
    }
}