fix: allow signing from safepal (#5862)

src/utils/signTypedData.ts

@@ -15,13 +15,27 @@ JsonRpcSigner.prototype._signTypedData = async function signTypedDataWithFallbac
   const address = await this.getAddress()
 
   try {
-    return await this.provider.send('eth_signTypedData_v4', [
-      address.toLowerCase(),
-      JSON.stringify(_TypedDataEncoder.getPayload(populated.domain, types, populated.value)),
-    ])
+    try {
+      // We must try the unversioned eth_signTypedData first, because some wallets (eg SafePal) will hang on _v4.
+      return await this.provider.send('eth_signTypedData', [
+        address.toLowerCase(),
+        JSON.stringify(_TypedDataEncoder.getPayload(populated.domain, types, populated.value)),
+      ])
+    } catch (error) {
+      // MetaMask complains that the unversioned eth_signTypedData is formatted incorrectly (32602) - it prefers _v4.
+      if (error.code === -32602) {
+        console.warn('eth_signTypedData failed, falling back to eth_signTypedData_v4:', error)
+        return await this.provider.send('eth_signTypedData_v4', [
+          address.toLowerCase(),
+          JSON.stringify(_TypedDataEncoder.getPayload(populated.domain, types, populated.value)),
+        ])
+      }
+      throw error
+    }
   } catch (error) {
+    // If neither other method is available (eg Zerion), fallback to eth_sign.
     if (typeof error.message === 'string' && error.message.match(/not found/i)) {
-      console.warn('eth_signTypedData_v4 failed, falling back to eth_sign:', error)
+      console.warn('eth_signTypedData_* failed, falling back to eth_sign:', error)
       const hash = _TypedDataEncoder.hash(populated.domain, types, populated.value)
       return await this.provider.send('eth_sign', [address, hash])
     }