[Bug]: React Context Race Condition in Vite Module Federation with Manifest

[larevalos]

Describe the bug

Bug Report: React Context Race Condition in Vite Module Federation with Manifest

Environment

• React: 18.3.1
• Vite:
• @vitejs/plugin-react: 4.3.4
• @module-federation/vite: 1.2.6
• TypeScript: 5.6.3
• OS: Windows
• Mode: Issue occurs only in production/build mode

Description

When using Module Federation with Vite in a React application, an intermittent race condition occurs when consuming remote modules through the mf-manifest.json approach. This race condition causes React contexts to fail, resulting in hook errors because React isn't fully initialized before federated components try to use context providers.

The issue only occurs in production/build mode. Development mode (both host and remote) works correctly.

Error Details

Multiple React-related errors occur, all indicating that React context is not properly initialized:

1. React Context Null Error:

Uncaught TypeError: Cannot read properties of null (reading 'useContext')
    at react_production_min.useContext (react.production.min.js:24:495)
    at ApolloProvider (ApolloProvider.js:8:25)

2. Hook Errors such as:

useEffect, useRef etc is undefined

3. Error with my context providers not being able to share instance between host and remote:

Root Cause

The race condition appears to be in how the mf-manifest.json approach loads shared dependencies. The manifest approach creates timing issues where host React contexts aren't fully initialized before remote components try to access them.

These timing issues appear to be exacerbated by the asynchronous nature of manifest-based loading compared to direct remoteEntry.js loading.

Workaround

I used the remoteEntry instead of manifest. What I lost there is that I was generating the remoteEntry in the remote app with a hash in the name on every new build. If I want to reference the remote entry with hash in the host I will have to find a workaround for that so that I won't need to update anything in the host application on every new build.

Steps to Reproduce

I couldn't reproduce the issue in smaller apps, they work!! It only happens in a bigger app where there are a lot of shared dependencies.

Version

6.2.5

Reproduction

I couldn't create a minimal reproduction

Relevant log output

Validations

• Read the docs.
• Read the common issues list.
• Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.
• The provided reproduction is a minimal reproducible example of the bug.

[gioboa]

Hi @larevalos , I see, thank you for your feedback.
Without a basic example it's really difficult to solve the issue. You have everything in your local machine to reproduce it so you can try to find a solution for that. You can change and debug files in the node_modules, it's the easiest way to start. Thanks

[larevalos]

Hi @gioboa , I'll find some time in these days and I'll try to find a solution and/or reproduce get a minimal reproducible example. Cheers

[pcfreak30]

@larevalos this feels very heavily similar to some stuff I ended up dealing with. After a lot of wasted energy I learned for my needs react bridge was not needed.

If you create multiple react roots you will get in a very complicated setup to the point I created an entire system to track react contexts and re-provide them in every single react root.

I used MF as a plugin system meaning only 1 index.html exists.

So if this sound familiar I hope it helps, else give more details as i spent an insane amount of time around react contexts and the framework...