Check of seed looks different on prater & mainnet

[stefa2k]

Using version v1.4.0-6b621ba the screen of the verification of the seed phrase looks differently on mainnet and prater:

Mainnet looks like this:

Prater looks like this:

[remyroy]

It's meant to be this way. We wanted a stronger confidence that the user actually wrote down their mnemonic for mainnet.