I have tried several times on several websites with JoomlArt templates and the Media Pop-ups simply don't work. I followed the instructions in a YouTube video that was pretty straightforward, I even double-checked to make sure that pop-ups are not blocked. Nothing. Clicking on an image set to use a lightbox does nothing.

Here is the page: only the first image has the pop-up set. I noticed another post where you examined the HTML and I'm hoping you can spot something that I can change to make this work since I'm paying for a subscription.

https://www.tooliewebclass.com/activity-reports

Thanks Ryan!

Ah, take of the https, use http://, this is a draft website and I didn't bother to install the SSL certificate.  http://www.tooliewebclass.com/activity-reports

Ugh!! The joys of Joomla. I had moved it into a submenu, my apologies!

http://www.tooliewebclass.com/about-us/activity-reports

OMG that worked instantly! Thank you! I have wanted to use this lightbox effect but couldn't figure out why it would not work. 

For the benefit of others who use the JoomlArt templates with the T4 Framework, here's where to turn OFF that compression. In System | Site Template Styles | Global Settings under CSS & JS Optimization, turn off the CSS Optimization. For good measure. I also turned off the JavaScript compression.