We have the same problem. Our iOS and iPad app is built with WKWebView technologies and on iOS 15 and iPadOS 15 we now have huge problems with performance and stability because of this GPU option by default (on the previous iOS/iPadOS versions it's fine).
And we couldn't find a way how to turn this GPU option off in the app. Apple team, we need your help with this, a lot of users struggle.
TolyaF
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