Professional window cleaner here and I just saw this. Sos pads will scratch glass, do not use an sos pad on glass. You can use a very sharp razor blade but wet the glass down first or it will scratch glass too. Bartenders friend is a great product for this as well as stove bright. You should use the liquid versions not the powdered version as they will also scratch glass. If using steel wool only use 0000. You probably don't know you have been ruining the glass slowly over time by using sos pads and kitchen scrubbers but you are. The grease and carbon gets into the scratches and then becomes very hard if not impossible to get clean. Ammonia is the window cleaner's friend. A way better than windex cleaning solution is made with a little dawn dish soap, a good size splash of ammonia and a half gallon of water. I like to use the white scrubber pads which are for easily scratched surfaces. Vinegar is an acid and very good at getting hard water off of glass. Ammonia cuts grease. Hope this helps. I just hate going to a new house to do the windows and seeing sos pad scratches all over the dang windows. The best bet for keeping that glass clean on the smoker or woodstove is to clean it very often. Just get in the habit of cleaning it after every smoke.