On iOS 14 MGLAnnotationView slows down map significantly

[flashspys]

The addition of even one custom MGLAnnotationView make the map unusable. The attached image shows the profiler where the mapbox rendering call is taking the most of the cpu. There is only a basic map showing one custom annotation. On iOS 13 this runs butter smooth. The Map is displayed via a UIViewRepresentable in SwiftUI.

Steps to reproduce

1. On iOS 14, create a MGLMapView and display one custom MGLAnnotationView.

Expected behavior

Map runs smooth

Actual behavior

Map is unusable slow

Configuration

The used custom MGLAnnotationView:

class CustomAnnotationView: MGLAnnotationView {
    override func layoutSubviews() {
        super.layoutSubviews()
        layer.cornerRadius = bounds.width / 2
        layer.borderWidth = 2
        layer.borderColor = UIColor.white.cgColor
    }
}

Mapbox SDK version: 6.0.0
iOS versions: iPad OS 14 / iOS 13.6
Device/simulator models: iPad Pro 1st Gen (iOS 14 device) / iPhone Xs (iOS 13 device)
Xcode version: 12.0 b2

[flashspys]

Wrong repo, I'm sorry. Reopened here: mapbox/mapbox-gl-native-ios#350