I noticed yesterday that one of our top bar hive observation windows has quite a few wax flakes stuck to the glass. Since they were still there this morning, i'm assuming the bees aren't all that interested in cleaning it up. Has anyone else dealt with a similar issue? Is it a "just live with it" kind of thing, or is there a safe way to "scrub" it off? The windows aren't actually glass, so i don't think scraping is an option.