And Shopify didn't fix it yet, although a lot of people work with safari browser. It is sad, Shopify doesn't work on optimization of the second browser (17.19%) in the world.

The problem is in the operation of the customizer with the "Prevent cross-site tracking" setting enabled in the Safari browser. In order for the customizer to work, you need to disable it, which I think is very bad for the security of the device and ...

The issue here is that something is activating security mechanisms in the Safari browser, so it's not about cache or cookies. It's not a Safari issue, it's a Shopify issue that didn't care about developing with this browser.

I have the same issue

It works. Thanks a lot.