Does your site use HTML5 and have a search form? One of our current Drupal 7 projects does, and we discovered today that WebKit provides its own styles for HTML5 input fields marked with an attribute of type=’search’. For those who need an example, this is the kind of thing you see:
See the small, blue cross?
This was rather hard to track down as the usual DOM inspectors do not report it and it only appears when you type something in the input field… this had all the hallmarks of a client side script adding a background image. However, this isn’t directly caused by anything in your source code - it’s your browser.
We did a bit of research and found a great article over at css-tricks.com, which explains this in more detail and shows you how you can disable or alter this browser feature.