Ensure message correctness in extension

[jonathanKingston]

Asana Task/Github Issue: https://app.asana.com/1/137249556945/project/1201614831475344/task/1211099580633727?focus=true

Fixes: #1900

Description

I think this issue is due to tab restoration in the service worker mv3 handling code in Firefox code only and only when the extension is updated (hence a new bout of reproductions).

I've done the following:

• Short circuited the init code when we get an invalid message, we can't do much in this scenario. The extension side needs to investigate this. These messages are likely more corrupt than just the enabledFeatures missing, so we just shouldn't risk breaking the page.
• Added typing to the isFeatureBroken method which would have prevented this exact issue.
• Handled the undefined enabledFeatures case in this method.
• Split out the logic as it was getting a little unreadable.

As a perf benefit:

• Short circuited the update logic just for the CTL feature as it's not required so it cuts out many function calls with checking listenForUpdateChanges

Testing Steps

• Visit various pages and validate no error is seen.
• Also visit https://privacy-test-pages.site/privacy-protections/click-to-load/ and ensure it's working as expected.
• Ensure https://osmand.net/map/plan/#15/46.1266/5.2599 has no warnings.

Checklist

Please tick all that apply:

• I have tested this change locally
• I have tested this change locally in all supported browsers
• This change will be visible to users
• I have added automated tests that cover this change
• I have ensured the change is gated by config
• This change was covered by a ship review
• This change was covered by a tech design
• Any dependent config has been merged

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[github-actions]

Temporary Branch Update

The temporary branch has been updated with the latest changes. Below are the details:

• Branch Name: pr-releases/pr-1907
• Commit Hash: b3225813262a212ec32f3f6e4a61aa82b605b06d
• Last Updated: August 20, 2025 at 11:11:21 AM UTC
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[github-actions]

[Beta] Generated file diff

Time updated: Wed, 20 Aug 2025 11:11:36 GMT

Android

    - android/autofillPasswordImport.js

• android/brokerProtection.js
• android/contentScope.js

File has changed

Apple

    - apple/contentScope.js

• apple/contentScopeIsolated.js

File has changed

Chrome-mv3

    - chrome-mv3/inject.js

File has changed

Firefox

    - firefox/inject.js

File has changed

Integration

    - integration/contentScope.js

File has changed

Windows

    - windows/contentScope.js

File has changed

[dharb]

Looks good 👍