fix: detect imtoken injected provider by browser

.unipi/docs/fix/2026-06-04-imtoken-injected-provider-detection-fix.md

@@ -0,0 +1,33 @@
+---
+title: "imToken in-app browser cannot connect after deeplink — Quick Fix"
+type: quick-fix
+date: 2026-06-04
+---
+
+# imToken in-app browser cannot connect after deeplink — Quick Fix
+
+## Bug
+
+After Chrome opens imToken's in-app browser, wallet login cannot complete and the wallet debug panel shows `connected: no`.
+
+## Root Cause
+
+The frontend looked for an injected wallet provider using the wallet-specific `isImToken` flag. Some imToken mobile versions inject a usable EIP-1193 `window.ethereum` provider but do not expose `isImToken`, so `getInjectedWallet("imToken")` returned `null`. That prevented the imToken direct-login path from using the injected provider and left the flow disconnected.
+
+## Fix
+
+Added a narrow imToken in-app-browser fallback: when the requested wallet is `imToken`, no provider has `isImToken`, but the user agent indicates imToken and `window.ethereum` exists, use the injected provider.
+
+### Files Modified
+
+- `src/wallet/injected.ts` — adds imToken user-agent fallback for injected provider detection.
+
+## Verification
+
+- `npx tsc --noEmit`
+- `npm run format:check`
+- `npm test`
+
+## Notes
+
+This fallback is limited to imToken browser user agents to avoid changing MetaMask or TokenPocket provider selection behavior.

src/wallet/injected.ts

@@ -138,6 +138,11 @@ export function getInjectedEthereum(): EthereumProvider | null {
   return maybeWindow.ethereum ?? null;
 }
 
+function isImTokenBrowser(): boolean {
+  if (typeof navigator === "undefined") return false;
+  return /imtoken/i.test(navigator.userAgent || "");
+}
+
 export function getInjectedWallet(kind?: WalletKind): EthereumProvider | null {
   const ethereum = getInjectedEthereum();
   if (!ethereum || !kind) return ethereum;
@@ -150,7 +155,15 @@ export function getInjectedWallet(kind?: WalletKind): EthereumProvider | null {
     if (kind === "imToken") return provider.isImToken;
     return false;
   });
-  return match ?? null;
+  if (match) return match;
+
+  // Some imToken mobile versions inject a usable EIP-1193 provider without
+  // setting `isImToken`. Inside the imToken in-app browser, prefer the injected
+  // provider instead of falling back to WalletConnect, which can leave the UI at
+  // connected:no on China networks.
+  if (kind === "imToken" && isImTokenBrowser()) return providers[0] ?? ethereum;
+
+  return null;
 }
 
 export async function getConnectedInjectedAddress(