u/SweetChardonnay

I'm installing a few lightweight shelves along the top of a wall currently acting as a projector screen. Because of this setup, visual design makes me want to place the L-bracket on the top side of the shelf, freeing up space below for the projector. The shelf and cat together can't be more than 15lb, divided between three brackets. Is this safe?

The other nasty variable: it's a plaster wall. I have Tapcon screws and anchors, but is this combo of weaker support a dealbreaker?