[BUG] Adding a key to a Blocto managed wallet renders the wallet unusable

[cybercent]

---

Note:
This is an issue with the Blocto wallet backend on Flow.
I posted this issue here as there is no public repository for Blocto wallet backend.

---

Reproduce

1. Go to Flow port and add a new key to your Blocto wallet.
2. Send any transaction.
3. The transaction will fail with an invalid signature error.

Issue

It appears that Blocto assumes that:

• a blocto wallet has only 3 keys and
• all keys are managed by Blocto

Fix

Instead of using keys.last and assuming the key is managed by Blocto, either

• use keys[2] (when account was created by Blocto)
• or check if the key at a specific index is a managed by Blocto before signing

[scottphc]

Hey, this issue is not releted to this repo and the root cause is from fcl.js onflow/fcl-js#1679. So let's close it for now.