Current behavior

After upgrading React Navigation packages, our Legacy Architecture app crashes when navigating to screens inside nested navigators (bottom tab -> native stack), with runtime errors like:

• Property 'WeakRef' doesn't exist
• equivalent WeakRef not found / undefined errors

This appears tied to the @react-navigation/core@7.16.2 change:

"use a weak ref instead of mutating params to avoid errors when it's frozen"

In nested navigation flows where params are consumed, core now calls new WeakRef(route.params). In our runtime, typeof WeakRef === "undefined", so it hard-crashes.

A key point: this can happen even when app code pins an older @react-navigation/native line, because /native allows a semver range for /core and installs can resolve a newer /core that includes this behavior.

Observed behavior:

• root stack navigation may still work
• nested tab -> stack navigation paths crash

Expected behavior

React Navigation should not hard-crash if WeakRef is unavailable.

Expected fallback behavior:

• feature-detect WeakRef before using it
• use a safe fallback path when missing

This would avoid runtime breakages in environments where /core resolves to versions requiring WeakRef but runtime support is absent.

Reproduction

https://github.com/wuppious/react-navigation-weak-ref-repro

Platform

• Android
• iOS
• Web
• Windows
• MacOS

Environment

• I've removed the packages that I don't use

Additional resolved dependency detail (repro repo):

• @react-navigation/core resolved to 7.17.1.

Additional environment detail:
Using React Native Legacy Architecture