What were the notable Meta updates?

Remove enableFabricRenderer() call from ReactInstanceManager (#56855), Remove enableFabricRenderer() call from DefaultNewArchitectureEntryPoint (#56854), and fix(ios): load RCTDefines.h first in React umbrella + drop submodule wildcard so RCT_* macros stay visible (#56862).

REACT NATIVE STRIPS FABRIC FLAGS, MAKES NEW ARCHITECTURE MANDATORY

By RepoJournal · Filed 06:03 UTC on May 19, 2026 · About Meta

React Native is baking the Fabric renderer into the core, ripping out the feature flags that let you toggle it off.

The New Architecture is no longer optional on canary. A series of commits landed overnight that delete the `enableFabricRenderer()` flag across the Android bridge [1], the instance manager [2], and the entry point [5], inlining `true` at every call site. This isn't a breaking change for most teams - Fabric has been the default since 0.84 - but it signals React Native is done with the toggle switch. The team also landed a critical iOS fix [3] that restores RCT macro visibility when building under `use_frameworks!` with prebuilt RNCore, which was breaking parse errors in consumer pods. A companion Android cleanup [4] removes a now-tautological assertion from ReactHostImpl. All internal changes, all behavior-preserving. This is cleanup work, but it's the kind that only ships once you're confident the foundation is solid.

Action items

→ If you build iOS under use_frameworks! with RCT_USE_PREBUILT_RNCORE=1, pull the latest to restore macro visibility [ref:2] facebook/react-native [immediate]
→ Verify your Android code doesn't rely on disabling Fabric via feature flags - that path is now gone facebook/react-native [plan]

References

[1] Remove enableFabricRenderer() call from ReactInstanceManager (#56855) facebook/react-native
[2] Remove enableFabricRenderer() call from DefaultNewArchitectureEntryPoint (#56854) facebook/react-native
[3] fix(ios): load RCTDefines.h first in React umbrella + drop submodule wildcard so RCT_* macros stay visible (#56862) facebook/react-native
[4] Remove enableFabricRenderer() assertion from ReactHostImpl (#56856) facebook/react-native
[5] Inline true for fabricEnabled in DefaultNewArchitectureEntryPoint (#56882) facebook/react-native

Quick answers

What shipped in Meta on May 19, 2026?: React Native is baking the Fabric renderer into the core, ripping out the feature flags that let you toggle it off. In total, 15 commits and 1 releases landed.
What were the notable Meta updates?: Remove enableFabricRenderer() call from ReactInstanceManager (#56855), Remove enableFabricRenderer() call from DefaultNewArchitectureEntryPoint (#56854), and fix(ios): load RCTDefines.h first in React umbrella + drop submodule wildcard so RCT_* macros stay visible (#56862).

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