It depends on what year you're working on. Most years have the vent window frame reproduced along with the "door runs", and various other bits and pieces. If you've removed the chrome strip from the top and rear of say, a 67 door glass, then you need to stop by a local glass+windshield shop. To reinstall that particular trim you need "packing" material. It's generic and most glass shops have a big roll or box of it.
Put the year and body style of your car in your profile and others don't have to guess what you're working on.