[fcl-wc] Session requests using deep links are not opening on Safari mobile

[gregsantos]

Issue opening wallet on session request (Safari Mobile)

When (default) setting of Safari mobile is set to Block pop-ups, deep links to wallet/browser quietly fail. Popup will be blocked if called in an async function. FCL needs to asynchronously connect and receive a URI for pairing before opening the deeplink. Need a solution that works and doesn't leave an empty window/tab behind.

Definition of Done

• When authn request is sent on mobile, Dapp uses universal/deep link to open wallet (if installed) or new browser tab with install instructions.

[gregsantos]

There are several recent reports of issues on this front. Working to solve this with the best UX possible.

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Issues referencing this bug and potential fixes

• [Sending transactions on iOS shows a deep link prompt after first attempt](https://github.com/WalletConnect/walletconnect-monorepo/issues/1165)
• optimal sign-in strategy for dapps with iOS mobile browser #536
• [fix: ensure blank tab isn't left behind after connecting on iOS](https://github.com/rainbow-me/rainbowkit/pull/540/files)
• [Redirect from website to wallet and wallet to website is broken](https://github.com/WalletConnect/walletconnect-monorepo/issues/1405)

[gregsantos]

Released alpha.3 Still seeing some flaky behavior on Safari so working on an update