Oddbean new post about login | logout You will need to be on the latest GrapheneOS App Store, it may not have reached everyone yet. If you don't have it then try select Beta and update. You are free to set it back to Stable after updating.
For outside GrapheneOS there's https://accrescent.app
Accrescent is alpha software (in terms of features) and likely wouldn't be appropriate to distribute it wider without further improvement. It is the maintainer's choice. It would be better for the future.