Since iPadOS 18.x WKWebView seems to have a bug within its Fullscreen API (which can be enabled via WKPreferences.isElementFullscreenEnabled). This bug has the effect that websites trying to make an element (for example a video player) fullscreen fail to do so. This does not always happen, most of the time the fullscreen mode does work fine, but sometimes (far too often to be ignored) it does not. If an instance of WKWebView shows this issue, it can not be "fixed" by reloading the page or loading other pages, this issue exists in this instance forever.
My App is a web browser App so I can create and remove WKWebView instance easily (by opening or closing Tabs). And there are times where I never see this bug, and times where ever other tab shows this bug. It's totally unreliable.
The App does not show any issues at all when running under iPadOS 17 or older. The issue is only present under iPadOS 18.x.
After some testing I've found out that when the bug has affected an instance of WKWebView, the JavaScript call element.requestFullscreen() will work if the element is a video element, but does no longer work if it is another element (like a DIV). If an instance of WKWebView is not affected by this bug, element.requestFullscreen() will work for all HTML elements.
Does anyone has experienced this bug as well? And maybe found a workaround? Or maybe found a pattern which helps to find out what exactly is triggering this bug?