This is a sample that uses google_mobile_ads to show MREC Ads inside a ListView.

It wraps the AdWidget in a custom widget with AutomaticKeepAliveClientMixin and wantKeepAlive=true.
This way the Ad is kept alive while scrolling the content without rebuilding / reload hiccups.

It also uses

AdWidget.optOutOfVisibilityDetectorWorkaround = true;

because we use Flutter >= 3.7.0

To demonstrate rendering performance issues from iPhone 12 onwards (tested on iPhone 12, 12 Pro, 13 Pro, 14 Pro).

While scrolling on an iPhone 12 Pro we see strange stuttering (vsync?) with some slow raster phase that causes the frame rate to be unstable around 53/55 fps and sometimes drops to 48 fps.

The absurdity is that on iPhone 7 and iPhone 7 Plus the framerate is mostly stable with a lowrate of 58/59 fps (same on iPhone 11).

We're using this use case with google_mobile_ads because it's a common use case that I also got in a production grade app.

But probably the issue isn't of google_mobile_ads but in the handling of PlatformViews and WebViews inside Flutter.