By the way, Yubico recently released firmware 5.8. Usually the first Yubikeys go on sale about 2-3 months later. Whether it is worth waiting can be read on Yubico, in any case, as most people know, a firmware upgrade is not possible with Yubikeys

The only binding information can be provided by the retailer. Galaxus does not do this, others do. I would buy where the firmware version is specified. Even if a customer confirms it, this relates to their purchase and may vary with their next purchase. Especially with Galaxus as they often have multiple offers of one item