Custom attributes

To add a custom attribute, such as "alt", to a source, add to the <a> element an attribute with the "data-" prefix:

<a data-fslightbox="gallery" data-alt="An example description." href="/Image.jpg">
	Image
</a>

Any attribute can be added:

<a data-fslightbox="gallery" data-alt="An example description." data-foo="bar" href="/Image.jpg">
	Image
</a>

<!-- The rendered source -->
<img src="/Image.jpg" alt="An example description." foo="bar">