There is a rectangular tab button at the bottom. What is it for?
That’s an airgap switch. Some light switches have them. When you pull it out it will completely disconnect the device from the electrical current. Then you push it back in to reconnect it. It’s used for resetting or sometimes if you’re working on it. The GE switches also have these.
Look down towards the bottom of the support page for the GE switches and it has a picture and explanation:
That’s an airgap switch. It kills power to the switch itself, and to anything on the load side of the switch.
Crap, still not fast enough to beat @JDRoberts, and I even had less to say!
Talking is faster than typing!