Shapes with layout=below still prevent hovering over traces

I’m having an issue with shapes added to a plot.
Even though I’ve set layer to below (which I understand means the shapes will be drawn under the traces), I still get no hover functionality on points in the trace if the shape overlaps them.

You can see that behaviour at https://plotly.com/~fabre.lambeau8688/106/.
When hovering over the middle part of the traces (where the green box overlays the traces), I don’t get spike lines and hover labels. When hovering the traces on the left or right of it, standard behaviour…