Make Chrome display alt text for images again!
Did you know that Chrome doesn't display alt text tooltips for images anymore?
alt fixes that!
How it works:
There is a behavior in Chrome (which is arguably a bug), and that is that hovering your mouse over an image (img node) no longer displays that image's alt text. However, Chrome does display title text! So we copy the alt text to the title attribute, and viola! alt text is back!
alt uses jQuery.on, so it will apply to all images in a document—even those loaded dynamically!
alt does NOT copy over the title attribute if it already exists. This way we work with modern sites like XKCD which are correctly using the title attribute as well as sites like Facebook which intentionally leave alt and title blank sometimes in order to prevent a tooltip.