Yes, black fiberglass tissue can be used for cleaning windows. It is a durable and non-abrasive material that effectively removes dirt and grime without scratching the glass surface. The fine fibers can reach into small crevices and effectively clean the window. However, it's important to ensure that the fiberglass tissue is clean and free from any debris or particles that could potentially scratch the glass. Always test a small, inconspicuous area first to ensure it doesn't damage the window.