Despite having “User Choice”, it will absolutely try to open that classic customization and you’ll get that access message.
Not really a “user choice” now is it?
I guess it’s a bit more nuanced than that.
What I found to work was setting the menu to User choice and setting each client to be “Classic” (this can be done with the dashboard I posted around here somewhere), then when they open a screen in the client, it should open the classic only. When they open it in the web browser, it should open Kinetic.
I only tested this with dual customizations (classic and kinetic customization set on the same menu), so I’m not sure how it will react if there’s no kinetic layer and you try and open that screen in the web.
This also won’t be a great solution if you use the shudder embedded browser.
Moral of the story… @timshuwy we need a better solution for this dual screen crossover thing most of us are living in.