I often find myself opening projects with query or range conditions applied to the layers. Or needing to apply them myself.
Currently one must open the properties of each layer to check if a query, range, join etc. has been applied. I would find it handy if there was a visual indicator to let me know at a glance what layers have what applied. Would also help to remind me to remove conditions before calculations.
I imagine I would not be the only one who receives lots of projects or is forgetful. For bonus points hovering over the icon would show its equation.