How Firefox Weather Extensions Handle Your Location Data

Weather extensions for Firefox need location data to show relevant weather. How they handle this varies significantly — and understanding it helps you make a better privacy decision about which one to install.

How Browser Location Works

When a Firefox extension requests your location, it goes through the browser's geolocation API:

navigator.geolocation.getCurrentPosition(
  (position) => {
    const { latitude, longitude } = position.coords;
    // Extension does something with this
  }
);

The browser (Firefox) controls this:

1. The first time the extension calls this, Firefox shows a permission popup
2. You can grant, deny, or dismiss the popup
3. You can revoke the permission at any time: address bar lock icon → Site Settings → Location

This is fundamentally different from mobile apps, which request OS-level location access that can operate in the background.

What Happens After the Extension Gets Your Coordinates

This is where extensions differ:

Privacy-respecting approach: coordinates → weather API → forecast data displayed. Nothing else. The extension stores the forecast data locally; your coordinates are not stored.

Privacy-concerning approach: coordinates → analytics service (logging where you are and when) → weather API → forecast data displayed. Your location history is being built somewhere.

The most concerning approach: coordinates → the developer's own server → weather API → forecast data. The developer has a record of your location and can associate it with other data they may collect.

How to Check What an Extension Does

For open source extensions: read the code.

For Weather & Clock Dashboard (MIT open source):

• View the background script on GitHub
• Find where navigator.geolocation is called
• Follow the coordinates to see where they're sent
• Verify the only destination is a weather API endpoint

For closed source extensions: look at the privacy policy. If there's no privacy policy, that's a red flag. If the privacy policy says "we share data with partners" or "we use data for analytics," that's what happens.

The Permission Scope Difference

A new tab extension that only runs when you open a new tab gets your location only when the new tab is open. It cannot silently track your location in the background.

Compare to a mobile weather app with "Allow always" location permission: that app can check your location continuously, even when you're not using it.

The browser's permission model provides meaningful protection that mobile OS permissions often don't.

Checking Permissions on Any Installed Extension

1. Go to about:addons in Firefox
2. Click any installed extension
3. Click the "Permissions" tab
4. Review what the extension can access

For a weather-only extension, you should see:

• ✓ tabs (required to replace new tab)
• ✓ Optional: geolocation (for weather)
• ❌ NOT <all_urls> (no reason to access every website)
• ❌ NOT clipboard (no reason to access clipboard)

Weather & Clock Dashboard uses only tabs and optional geolocation. If the permissions page shows anything else, that would be unexpected.

The Short Version

If you want weather on your new tab with the best privacy profile:

1. Choose an open source extension (you can verify what it does)
2. Verify it uses tabs + geolocation permissions only
3. Grant geolocation permission only when you're comfortable with it
4. Read the relevant code to confirm coordinates go only to a weather API

Weather & Clock Dashboard checks all four boxes.