Old wash cloths & towel
Optional – painters tape
Cover the window with baking soda.
Squirt the baking soda with a vinegar and water mixture. Do a ratio of 1:10, 1 part vinegar, 9 parts water
You want the baking soda to get damp but not drenched. You are making a paste.
Get an old wash cloth wet and squeeze out the excess.
Start scrubbing the paste with the damp wash cloth. Gentle scrubbing is fine, it doesn’t have to be hard scrubbing.
Keep working around the glass, if you see a black spot scrub at it a bit. It won’t take a ton of effort.
Also scrub the black metal around the window and cleaned that up as well.
Clean up your mess with vacuum cleaner, but you could use a small broom and dust pan.
Geet a fresh old wash cloth wet, squeeze it out, and wipe it one more time.