Window Bird Feeder

I designed a bird feeder so that my son could watch the birds come up and eat at the window. I used something similar to these suctions cups off of Amazon (https://www.amazon.com/Sponge-Holder-Suction-Replacement-Kitchen/dp/B0BXJF5H48/ref=sr_1_8?crid=2O8USA1JJ2DQ1&keywords=suction+cups&qid=1701272815&sprefix=suction+cups%2Caps%2C158&sr=8-8)