It’s summer. Odds are if you don’t have central air, you’ve got an AC unit sticking out of at least one window.
Do you have any idea how easy it is for a burglar to push that into your house and climb in through the window?
Most air conditioners have holes where you can screw them right into the window frame. Do that. It makes it so they can’t push the unit into the house.
Also do this. Screw corner brackets into the window frame of the top pane, preventing the bottom pane from opening any further than it is for the AC unit–and of course preventing the top pane from opening at all. (See the picture below.)
Now you can have air conditioning and a secure window all at the same time. You’re welcome.