Tracking a website for updates isn’t hard, it might prove a bit tricky should the site lack an RSS feed but it is nevertheless possible. NotiPage, reviewed just yesterday, is one way of monitoring individual pages that lack RSS Feeds but if your needs take you further down to monitoring individual elements, AlertBox is the answer. AlertBox is a Firefox extension that lets you pick individual elements on any web page and monitor them for changes. Changes can be anything from ratings, number of comments or number of posts in a particular category.
The extension adds a bell icon button next to the URL bar. The button will have to be dragged out and added to the navigation bar from the customize toolbar box. The button toggles the extension on & off.
When clicked, the extension divides the window in to two panels; the lower panel is dedicated to the extension’s functionality while the upper panel is reserved for viewing the web page. Mouse over different elements on the page and a solid black border will appear around each element. Click the element you want to monitor for changes, enter a name for the alert and select how often the extension should check for updates. You can select one of the given time options from the dropdown menu. Click Add Alert to add the alert.
To view all alerts that you’ve added, to remove or modify one of them or manually check for updates, click Show my Alerts in the extension panel. Clicking on any one of the alerts shows its last saved state. To delete an alert, select it and click Remove Selected Alerts. You can modify the interval between checks for any of the alerts and enter a custom time interval. Click the time interval for a particular alert and a dropdown will appear. Pick a time interval from the options or choose custom to enter a different time. Click Save to apply the changes or Discard to cancel them.
The extension works in the background and whenever it detects a change in one of the elements that you’ve created an alert for, a desktop notification pops up complete with an audio alert (a small bell sound). The notification tells you which alert it has detected a change for.
It can be extremely useful in cases where you might want to temporarily monitor a discussion thread on a website or a forum but would like to keep your inbox clean of emails alerting you to a new comment every two seconds.