I agree, I even created an issue about this on Jumble github repository.
nostr:npub1syjmjy0dp62dhccq3g97fr87tngvpvzey08llyt6ul58m2zqpzps9wf6wl Awesome! You've squashed the bug. Now the signed-in state persists across the browser sessions, or even after refreshing the browser tab. Thank you.
One more thing: you might want to implement a feature that would pop up profiles/accounts after typing @ as it does on other social media while tagging someone, and even on other #Nostr clients. By default, pressing @ could pop up the most frequently mentioned profiles, or it could do nothing. Upon pressing a single letter, it should pop up profiles matching that letter/character. Upon pressing the second, it should refine the matches and so on. Is this feature on your pipeline? This would increase the usability of #Jumble even more.