[Bug]: Keystone: Firefox when MM is open in pop-up view, clicking on Get signature in transaction confirmation opens MM in full screen

[Unik0rnMaggie]

Describe the bug

During a send transaction using Keystone QR account on Firefox browser, if pop-up mode is enabled, clicking Get Signature in transaction confirmation opens MM in full screen.
Clicking Get signature again works and the transaction is successful.

Unable to reproduce on Chrome

Expected behavior

Continue with pop-up view

Screenshots/Recordings

Send.pop-up.FF.prod.build.mov

Send.pop-up.Chrome.mov

Steps to reproduce

1. Connect QR wallet Keystone to MM FF browser
2. Switch to pop-up view
3. Start send transaction
4. Click Get signature
5. Notice MM opens in full screen view

Error messages or log output

Where was this bug found?

Live version (from official store)

Version

13.32.1

Build type

None

Browser

Firefox

Operating system

MacOS

Hardware wallet

Keystone

Additional context

No response

Severity

No response

[mm-token-exchange-service]

Triage Agent -- Classification

Severity: Sev2 (confidence: 0.85) ✅

This is a UI flow issue specific to Firefox when using QR-based hardware wallets (Keystone). The signature flow is disrupted by opening full screen instead of staying in popup, but the transaction can likely still be completed in the full screen view. It affects a specific subset of users (Keystone/QR wallet users on Firefox in popup mode). It's not a data loss or security issue, but it breaks the expected UX flow.

Size: size-M (confidence: 0.65) ⚠️ Advisory

This likely involves investigating how the QR signing flow triggers window/tab opening behavior differently on Firefox vs Chrome. The fix probably involves modifying how the QR popover/modal is opened during the signing flow to prevent it from triggering a full-screen redirect on Firefox. May require changes to the QR hardware wallet integration components and possibly browser-specific handling.
Not auto-applied -- confidence below threshold.

Team: team-accounts-framework ✅

Matched via area fallback: area-qr (no CODEOWNERS match)

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Root Cause Analysis

Affected component: QR hardware wallet signing flow / QR popover component

When the QR signing flow is initiated (clicking 'Get Signature'), the QR code display/scanner popover needs to open to facilitate the air-gapped signing process. On Firefox, this popover opening mechanism likely triggers a full-screen window open instead of rendering within the existing popup. This is likely because: (1) Firefox handles popup window dimensions and camera access differently than Chrome - the QR signing flow requires camera access to scan the signed QR response, and Firefox may require a full tab for camera permissions, or (2) the code that opens the QR popover uses window.open or triggers a navigation that Firefox interprets as needing a new tab/window, or (3) there's a platform check or environment detection (getEnvironmentType()) that incorrectly routes Firefox popup to full screen when the QR signing flow is triggered. The QR signing flow has two sub-components: a 'player' (displays animated QR for the hardware device to scan) and a 'reader' (scans the signed response via camera). Camera access in Firefox popups may be restricted, causing a fallback to full-screen mode.

Evidence:

• Issue is Firefox-specific, suggesting browser-specific behavior around popups or camera access
• QR signing flow requires camera access (reader component) which Firefox may handle differently in popup context
• KB notes that camera permission state tracking (CameraPermissionState) is used for QR-based hardware wallets
• The sign-request subflow has player and reader components that may trigger window management differently on Firefox
• The 'Get Signature' button initiates the QR code exchange flow which involves opening a popover/modal

Suggested Fix

Confidence: medium: likely but needs investigation - the exact file paths for the QR popover are inferred from KB context naming conventions, and the root cause (camera access vs window management) needs verification

Investigate the QR signing popover opening mechanism to determine why Firefox redirects to full screen. The likely cause is either: (1) camera access request in Firefox popup triggering a full-screen redirect, or (2) explicit logic that opens a full tab for QR operations. The fix should ensure the QR signing popover renders inline within the popup on Firefox, or if camera access requires full screen on Firefox, handle the transition gracefully and return to popup after signing.

Target files: ui/components/app/qr-hardware-popover/qr-hardware-popover.tsx, ui/components/app/qr-hardware-popover/enhanced-reader.tsx, ui/components/app/qr-hardware-popover/base-reader.tsx
Target functions: QRHardwarePopover, handleGetSignature, openPopup

Approach:

1. Search for any window.open, browser.windows.create, chrome.windows.create, or openFullScreen/expandView calls in the QR hardware wallet signing flow path. 2. Check if there's platform-specific logic (e.g., getEnvironmentType() or platform.openExtensionInBrowser()) that triggers full-screen on Firefox. 3. Look at the camera permission request flow in the QR reader - Firefox may not support getUserMedia in extension popups, causing a fallback to full screen. 4. If camera access is the issue, consider: (a) requesting camera permission before opening the QR reader, (b) using a different approach for Firefox popups, or (c) ensuring the QR popover renders within the existing popup DOM rather than opening a new window. 5. Check ui/components/app/qr-hardware-popover/ directory for the popover implementation and any browser-specific handling.

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Confidence threshold: 0.85. Labels marked ✅ were auto-applied. Labels marked ⚠️ are advisory only (below threshold).
To re-triage, remove the ta-bot-triage label and re-apply ta-needs-triage.
⚠️ Some dimensions could not be confidently classified. An engineer should review this issue.

[Unik0rnMaggie]

Present in v13.35.0 RC on Firefox browser:

Send.pop-up.FF.mov