[iOS] Deeplink + Confirmation Prompt issues

[darthmeme]

Describe the bug When any action requires the user to approve or reject said action (like sendTransaction) in MetaMask, more often than not the deeplink will re-direct to the AppStore instead of MetaMask even when it's installed. In addition, when finally opening MetaMask, half the time the confirmation prompt will never show.

To Reproduce Requirements: MetaMask mobile (signed in)

1. In Safari, go to https://web3modal.com/ and click on "Connect". Choose WalletConnect, and then MetaMask. Finally, approve the connection.
2. Once redirected back to the web app, click on eth.sendTransaction

Note: I used web3modal here cause it's easiest to reproduce, but I've reproduced this issue on my own app as well as other web apps such as OpenSea.

Expected behavior I expect the MetaMask app to open and the confirmation prompt for the transaction to show every time.

Instead I very often get redirected to the AppStore. And when I open MetaMask, the confirmation prompt doesn't show most of time. Although sometimes it does.

Smartphone (please complete the following information):

• Device: iPhone 12 Pro
• OS: iOS 15.6
• App Version: 5.4.0 (931)

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to be added after bug submission by internal support / PM Severity

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• Is this tech debt?