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concrete

Just tried pinch to zoom on one of my saved videos in Aves Libre. Can confirm it works and it meets your preferred criteria.

GrapheneOS version 2023072600 released:

https://grapheneos.org/releases#2023072600

See the linked release notes for a summary of the improvements over the previous release.

spring-onion once it's gone, it's gone.

Data is gone, but the fact that a profile has existed may persist.

Yes. Each profile is separately encrypted with its own keys - once it's gone, it's gone. See the faq for an in-depth explanation:

https://grapheneos.org/faq#encryption