plugins occassionally not working

hey guys i dont know if anyone out there can help with this problem, as this is really strange. The problem is that plugins like product image flipper and wp-featherlight just stop working sometimes. Like in one moment hey work, and i refresh the page and they dont work anymore.
WHen i click the link for the homepage it works usually but when i refresh it doesent?

No idea what this is, my website is https://humorfront.com
The “devided by zero” shirt should have a hover effect but it only works sometimes, you can try it yourself.

Cheers