I can't sign offchain transactions using the standard https://eips.ethereum.org/EIPS/eip-712

It happens in IOS.

Also, tried using the desktop application connected to the IOS wallet, and it also fails.

How to reproduce
I can provide Rinkeby tokens if it helps reproducing the issue.

1. Go to http://cowswap.exchange
2. Connect (injected wallet). Note, the app works in mainnet, but also Rinkeby and xDAI
3. Select any token pair
4. Approve sell token for selling
5. Try to swap. Swapping signs the transaction using EIP-712

Observed behaviour:

https://github.com/gnosis/gp-swap-ui/issues/710