Auto-Detecting Location Without Asking for GPS

For the Weather & Clock Dashboard Firefox extension, I needed the user's city without requiring the geolocation permission (which triggers a scary browser prompt).

Here is the approach I used.

The Problem with navigator.geolocation

The geolocation permission triggers a modal asking the user to share their precise location. For a new tab weather extension, this feels invasive. The user just wanted weather — they did not expect a location permission prompt.

Solution: IP-Based Geolocation

For weather purposes, city-level accuracy is enough. IP geolocation gives you the city without any user prompt:

async function getLocationFromIP() {
  const resp = await fetch("https://ipapi.co/json/");
  const data = await resp.json();
  return {
    city: data.city,
    country: data.country_name,
    timezone: data.timezone,
  };
}

This requires no permissions, no user prompt, and works in any browser extension context.

Privacy Considerations

IP geolocation does not require you to send the user's IP to a third party — the user's browser is already making the request to get their own IP info. However, you should:

1. Disclose this in your privacy policy
2. Cache the result to avoid hitting the API on every new tab open
3. Allow users to manually override their city

The Fallback: Let Users Type Their City

The most privacy-friendly approach is to let users type their own city:

// First-run setup
const { city } = await browser.storage.local.get("city");
if (!city) {
  // Show a setup screen asking for city
  showCityInput();
} else {
  loadWeather(city);
}

This is what the Weather & Clock Dashboard does — no automatic location detection, no permissions requested. The user types their city once and it is saved locally.

Which to Choose?

For a new tab extension where weather is secondary, manual input respects users the most. For a weather-first extension where accuracy matters, IP geolocation is the right trade-off.