What is GeometryReader and why shouldn't you overuse it?
The gist
GeometryReader is a container that passes a GeometryProxy into its closure: the size of the proposed space, safeAreaInsets and frame(in:) in the desired coordinate space (.local, .global, .named("scroll")). It is used when the layout depends on the available size: proportional columns, parallax, reading a position inside a ScrollView.
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