I download the apk file from Whatsapp website to install in GrapheneOS, and I've noticed that notifications for messages are very delayed from 15 minutes to no notifications at all until I turn on phone screen and then all of the messages come through. Is there other Whatsapp users with similar issues with functionality?
Signal functions good but there have been times of small delays with messages coming through to get a notification.
WhatsApp uses Google push notification service which is not available on GrapheneOS. Try to disable all battery restrictions for the app so it can check for notifications by itself but idk if it'll work still.