Currently, I am working on a pre-existing website called www.shopthethirdfloor.com. When using Internet Explorer, if you navigate to the products menu, select the search box, and then scroll down so that the search field goes underneath the menu overlay that appears, the search field remains hidden under the overlay while the cursor continues to blink in the location of the hidden input field. This issue seems to only occur in Internet Explorer. Additionally, both the search function and product display are within an iframe. It's possible that this behavior is due to a bug/feature specific to Internet Explorer, depending on whether you view it as a user or from Microsoft's perspective.