Indeed, the seed should never get online, not even for the printer (also mail, cloud, desktop are not proper places for storing).

And, important: after you generated the seed, wrote it for safe keeping and so on, write down 1-2 addresses (can go even to a text file), reset the HW once again, recover from the seed, match the addresses. This would ensure you don't come crying in 10 years that the seed you've written down doesn't give the addresses you expect.