Hello,

I have such an issue while using jQuery 3.5.1 with Test jQuery Updates plugin:
I can not use plus/minus buttons to setup quantity of product on the Woocommerce cart page when I switch on 3.5.1. jQuery version.
There is no error in dev. console.
When I choose "default" jQuery then it starts working again.
(jQuery Migrate a jQuery UI version does not affect it. I tried on Twenty Twenty template - the same issue.)

(Woocommerce v. 4.3.1, WP 5.4.2, GeneratePress 2.4.2)