[Due for payment 2026-03-04] [Onyx Audit] Remove canBeMissing from useOnyx

[fabioh8010]

Coming from #71202.

In order to simplify useOnyx API (and consequently Onyx) let's work on proposing the removal of some configurations we think are anti-patterns / unnecessary at this point.

The canBeMissing configuration logs an alert (also Growl alert in dev) if Onyx returns undefined for that subscribed key. It is purely for identifying cases where useOnyx should be returning data but it isn’t. I don’t think we ever invested in actually track down these missing data logs that are sent to BE, and most of the time its purpose is being bypassed by contributors.

I assume that at this point it’s pretty useless and we could raise a discussion to propose removing it.

[mountiny]

I assume that at this point it’s pretty useless and we could raise a discussion to propose removing it.

Let's discuss this with Ionatan for sure

[fabioh8010]

Got approval from Ionatan last week.

I will prepare a proposal this week.

[fabioh8010]

Updates:

• Posted proposal for internal review.

[fabioh8010]

Updates:

• Posted proposal for external review -> https://expensify.slack.com/archives/C08CZDJFJ77/p1770828347278359

[fabioh8010]

Updates:

• Proposal was accepted.
• WIP Draft PR is up -> Remove canBeMissing option from Onyx react-native-onyx#734