https://www.w3schools.com/jsrEF/met_element_requestfullscreen.asp
Fullscreen API requestFullscreen() Method
Well organized and easy to understand Web building tutorials with lots of examples of how to use HTML, CSS, JavaScript, SQL, Python, PHP, Bootstrap, Java, XML...
fullscreen apirequestfullscreenmethod
https://caniuse.com/?search=requestFullscreen
"requestFullscreen" | Can I use... Support tables for HTML5, CSS3, etc
"Can I use" provides up-to-date browser support tables for support of front-end web technologies on desktop and mobile web browsers.
can i usesupport tablesrequestfullscreenhtml5css3