jsFiddle is the perfect solution; it provides a custom environment (based on user selections) to test (or fiddle with) your JavaScript, HTML, and CSS code ... the page is the menu area where ...

We can also add drop-down menus to our HTML forms. We can use the select element to implement these drop-down menus. Input choices are in “option” elements as shown in the example below.

If you know a little bit about HTML, CSS, and JavaScript (or even just one of ... For this example, choose Some from the dropdown. We want this extension to work on every macworld.com URL, so ...