[Docs] Mini App wallet provider migration guide needed: Base App in-app browser (post-April 2026)

[schoolkamsergj]

Problem

Base App's April 2026 update changed how mini-apps are launched: they now open in a standard in-app WebView instead of a Farcaster mini-app host. This is a breaking change for any mini-app that uses @farcaster/miniapp-sdk for wallet access.

The current docs don't cover:

1. How to detect Base App in-app browser vs. true Farcaster embed (Warpcast)
2. How to fall back to injected EIP-1193 provider (window.ethereum / coinbaseWalletExtension) in Base App
3. The sdk.actions.ready() / sdk.wallet.getEthereumProvider() hang issue specific to Base WebView

This causes mini-apps to silently hang on transactions — no error, no timeout, just an indefinite loading state.

Suggested Addition

A "Wallet Provider Migration for Base App 2026" section in the mini-app docs covering:

Detection pattern

// Base App (post-April 2026) does NOT act as Farcaster mini-app host.
// sdk.isInMiniApp() returns false — use injected EIP-1193 instead.
async function getProvider(sdk) {
    const isEmbed = await Promise.race([
        sdk.isInMiniApp(),
        new Promise(resolve => setTimeout(() => resolve(false), 1000))
    ]);
    
    if (isEmbed) {
        return sdk.wallet.getEthereumProvider(); // Warpcast / true Farcaster host
    }
    
    // Base App or regular browser: use injected wallet
    return window.coinbaseWalletExtension 
        ?? window.ethereum 
        ?? null;
}

ready() timeout pattern

// In Base App, ready() never resolves — wrap with timeout:
await Promise.race([
    sdk.actions.ready(),
    new Promise((_, reject) => setTimeout(() => reject(), 5000))
]).catch(() => { /* continue, Base App doesn't need ready() ack */ });

Working Reference Implementation

This exact pattern was implemented and verified on Base mainnet in a real mini-app:

• Commit: schoolkamsergj/base-invaders@64fb7b2
• Live app: https://base-invaders-nine.vercel.app
• What was fixed: daily check-in and leaderboard transactions hanging indefinitely in Base App, working correctly in Warpcast

Impact

Any mini-app using @farcaster/miniapp-sdk for wallet transactions that:

• Was built before April 2026
• Relies on getEthereumProvider() from the SDK
• Is listed in Base App discovery

...will silently break for all Base App users without this migration.

Related SDK Issue

Filed upstream: farcasterxyz/miniapps#608

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Happy to contribute a PR with the docs addition if that would help.