Wix unfortunately rewrites the embed code that you provide and wraps it in code that does not support full screen. Wix members have been complaining about this for years but Wix has yet to remedy the issue. If this is going to be a problem, you can make an image load the media in a separate browser tab.
On my Wix site, why does my embedded video or presentation not go full screen?
Updated over 2 years ago