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

Xác định tài liệu về wallet của mini-app và trước tiên xem lại hướng dẫn hiện có về provider và SDK. Sử dụng hành vi được cung cấp của Base App và Warpcast, các mẫu timeout, upstream issue và reference commit để thêm phần migration; được coi là hoàn tất khi tài liệu giải thích việc phát hiện, injected-provider fallback và cách xử lý an toàn các lệnh gọi SDK bị treo.

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: https://github.com/schoolkamsergj/base-invaders/commit/64fb7b2b5b9f4e142d5d85642353fd4e62512cca
• 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

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