Auto-close wallet handoff tab after successful extension flow

[macterra]

Summary

After the React wallet hands a request off to the browser extension, the original wallet tab should be able to close automatically when the extension flow completes successfully.

Right now the wallet shows a good confirmation screen:

• "Opened in Archon Wallet extension"
• with Continue in Web Wallet and Close Tab

That is a solid fallback, but the remaining UX papercut is that users are left with an extra tab after the extension successfully completes the login/accept flow.

Goal

When a wallet request is handed off from the React wallet web page to the browser extension, the extension should close the original handoff tab automatically after a confirmed successful completion.

This should apply to:

• auth challenge flows
• credential accept flows
• alias accept flows

Why the extension should do it

A normal web page cannot reliably close an arbitrary tab opened by the user.
The browser extension can, because it has tab access and already receives the request from a specific source tab.

Proposed design

1. Add a handoff session id

When React wallet hands off a request to the extension:

• generate a handoffId
• include it in the page-to-extension message
• keep it associated with the source page state

2. Record the source tab in background

In the extension background script:

• store { handoffId, tabId, action, createdAt }
• keyed by the handoff session id

3. Close only on confirmed success

When the extension completes the auth/accept flow successfully:

• send a success message to background with handoffId
• background looks up the original source tab
• before closing, verify the tab still matches the expected wallet handoff URL/state if possible
• then call chrome.tabs.remove(tabId)

Safety checks

Only auto-close when:

• the extension flow succeeded
• the user did not cancel
• the original tab still appears to be the handoff page
• the handoff record has not expired

Do not auto-close when:

• the flow fails
• the flow is canceled
• the tab has navigated elsewhere
• the tab record is stale or missing

Open questions

• What is the best handoff id format and storage lifetime?
• Should the wallet tab include the handoff id in the URL, memory state, or both?
• What success event is the right trigger for auth vs credential vs alias acceptance?
• Should there be a user setting to disable auto-close?

Acceptance criteria

• After successful extension auth, the original wallet handoff tab closes automatically
• After successful credential accept, the original wallet handoff tab closes automatically
• After successful alias accept, the original wallet handoff tab closes automatically
• No auto-close happens on failure or cancel
• The feature is implemented by the extension/background, not by the web page alone