Set default shipping label size / printer

[t-design9]

Hello

How do I change default label size for printer?

I bought a thermal 4x6, installed it, and it works. But I can not correctly print labels from shopify. Because shopify always generates A4 format file and there is no way to change it... I found some older articles on the subject, and those advices do not apply to 2022 version of Shopify.

When I go to Settings->Shipping and Delivery, I can see that there are two label sizes available : A4 and 4x6. But there is no way to select anything there. They are just... shown, see pic 1. Test label prints fine for 4x6. But I can not select it for shipping label PDF to be generated in 4x6. So when I go to orders and select create label - it's always A4 size PDF, and then when you click print - it's a really mess when 4x6 printer selected, see pic2

Oh, and JPG or PNG files not supported, so I guess I can not show pic1 and pic2. Back to the stone age...