If you use [[embedvideo]] to embed a YouTube video on one page, then you include that page on a second page using [[include ...]], the video displays fine on the second page, but the control to view the video full screen is disabled.

To replicate this do the following:

1. Create a page, call it "test:source-video" and add the following content. On this page, you can click on the icon at the bottom right corner of the player to view the video full screen.

 [[embedvideo]]
 <iframe width="854" height="480" src="https://www.youtube.com/embed/_U14raZPF_w" frameborder="0" allowfullscreen></iframe>
 [[/embedvideo]]

2. Create a second page, call it "test:included-video" and add the following content. On this page, the icon at the bottom right corner of the player tells us that full screen is disabled.

 [[include test:source-video]]

This problem only started when YouTube switched to their new HTML5 video player. It wasn't a problem with the old Flash player.

Our site uses lots of includes, so this is a real show stopper…