I am sorry if this is actually an Elementor issue. I would guess it has something to do with how GP loads product tabs.
I have made a custom single product page using Elementor. Here I have two “Product Tabs” elements in two different sections of the page. Each product tab element is shown/hidden depending on whether it is a mobile/desktop device using the responsive settings in Elementor.
The problem is that only the last loaded product tab element is “active” after page load. In my case this is the version shown to mobile-devices. This means that if I load the page on a desktop I have to click the description tab on the product tab element to actually see the description text.