Thanks! I see, I was told I would need a "razor blade" and thought of Gillette razor blades! Would something like the one on amazon be ok? (See the link, can't add picture). It's for the job in the picture. Thanks again for your help.
Hi cesca, Do not use the one you have provided a link to, it may scratch the glass. Search for window scraper, they hold a replaceable backed razor blade. Regards S