We then introduce new values for the existing contain-intrisic-width and contain-intrinsic-height properties: from-element and from-element.
![iframe html code with size iframe html code with size](https://i.ytimg.com/vi/g-pGLS2TZ5E/maxresdefault.jpg)
Maybe that's best done by just expanding the property's type from double to (double or DOMString) at that time.
![iframe html code with size iframe html code with size](https://media.geeksforgeeks.org/wp-content/uploads/20210910162124/20210910161913.gif)
![iframe html code with size iframe html code with size](https://i.ytimg.com/vi/LxecgHeUMjM/maxresdefault.jpg)
The iframed page sets the requestedwidth="" and requestedheight="" elements on its element, to communicate the desired intrinsic size up to the containing page.The from-element indicates that the element's intrinsic size will be taken from whatever the contained page indicates. It can optionally provide an initial intrinsic size, in this case 500px 500px. The containing page styles the element with contain-intrinsic-size: from-element.This example illustrates the two-sided opt-in for this feature: