Read the tweet and their screenshot - they describe it as “a self-custodial…wallet” and while they do allow for self-custody (much better than most other Liquid wallets!) they just label the liquid balance as “Instant Payments (Liquid and Lightning)”. They don’t actually support Lightning, of course, only swaps. It’s not clear at all from any of their marketing or UI that this balance is, in fact, not self-custody.