Always Valid Lightbox is a Lightbox plugin whose markup adapts to the WP site's Doctype, in order to always provide valid HTML markup.
As of April 2026, Always Valid Lightbox is a WordPress lightbox plugin with 60 active installations and a 4.5/5 rating from 2 reviews. It has been downloaded 8.6K+ times in total. Requires WordPress 3.0+ and PHP false+. Available on WordPress.org since 2012. Last updated 13 years ago — may have compatibility concerns. Top alternative: Firelight Lightbox.
Always Valid Lightbox is a Lightbox plugin which can automatically add the HTML attributes needed to trigger the effect on content image links, so that
the user never has to add a class or an attribute to his content images in order to make the lightbox work.
Also, AVL allows the user to chose the attributes he wants inserted on his image links, depending on the Doctype declaration used in the website header.php template.
This way, the lightbox never generates markup validation errors at the W3C Validator test.
The jQuery lightbox effect is an adaptation based on David Ryan’s jQuery lightbox tutorial : http://dryan.com/articles/jquery-lightbox-tutorial/
| WordPress | 3.0+ requiredTested up to 3.4.2 |
| PHP | false+ required |
Plugin data sourced from WordPress.org. Analysis and metrics by PluginSift.