Hi Michael,

> so one thing I have to decide is whether filtering
> should only limit selections to the filtered items or
> whether it should limit both selection and deselection actions.

I'd always expect both selection and deselection, that's because all the other CAD programs I've used throughout my career work this way, the only difference between these and MoI is that the other programs use a modifier key with the mouse click to deselect.

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