It enables videos from various sources to be displayed in fullscreen mode. Be sure to include a link to the page where the video is embedded so that we can take a closer look at your page's source code. If you want to make an embedded video or other content go fullscreen with HTML, you may encounter some issues with different browsers and attributes. allowfullscreen is an HTML attribute, usually used within an iframe HTML tag.
If you're not sure if the above cases apply please contact us and we’ll investigate further. If I use this embeded code The Video having an option with popout (at the Upper Right Corner) and There is no full Screen Mode. We recommend removing all frame tags from your page’s source code.
Next, we’ll use CSS to make the iframe responsive. Frame elements cannot enter fullscreen, and neither can any iframes inside of them. That’s why very often we use the width and height attributes to set different size of an iframe. The iframe is contained within a frame.Try inserting the player outside of the container iframe or adding "mozallowfullscreen," "webkitallowfullscreen," and "allowfullscreen" to the container iframe. Browsers do not allow iframes to enter fullscreen if they are contained within other iframes without these fullscreen attributes. The player iframe is contained within another iframe that is missing the fullscreen attributes.The iframe embed code is missing the fullscreen attributes: "mozallowfullscreen,""webkitallowfullscreen," and "allowfullscreen." If you’re pasting your embed code into another application, make sure these values are being retained.Make sure the fullscreen button is toggled on under the Controls section. The fullscreen button will be hidden from the player in scenarios where fullscreen mode cannot be activated.