flutter – Why is this memory leaking?

In this example, each time I press “Click”, 50M of ram is allocated. It is never reclaimed, I can push 30 pages and take up 1.5gb, despite there only ever being 1 page on the nav stack. GC never kicks in. What’s going on here?

Flutter (Channel master, 2.1.0-11.0.pre.122, on Microsoft Windows (Version 10.0.18363.1440), locale en-US)

void main() {
  runApp(MaterialApp(
    home: MemoryTest(),
  ));
}

class MemoryTest extends StatelessWidget {
  final List<EdgeInsets> insets = List.generate(
    1000000,
    (index) => EdgeInsets.all(0),
  );
  @override
  Widget build(BuildContext context) {
    return Container(
      color: Colors.white,
      child: Column(
        children: (
          OutlinedButton(
            child: Text("CLICK"),
            onPressed: () {
              Navigator.of(context).pushReplacement(MaterialPageRoute(
                builder: (_) => MemoryTest(),
              ));
            },
          ),
        ),
      ),
    );
  }
}