The bug lies in the JavaScript code within the HTML file. Instead of using the correct innerHTML property to modify the content of a div element, it uses innerHtml, a typographical error.

Bug Description The code attempts to change the content of a div element using Javascript. It mistakenly uses innerHtml instead of the correct innerHTML property.

For those with a little JavaScript experience, try using the innerHTML property of the div tag to expand and contract outlines and add interactive help to your site.