FlagSwap Privacy Policy

Last updated: 20 July 2026

FlagSwap is a browser extension that lets QA engineers and developers override LaunchDarkly client-side feature flags in their own browser. This policy explains what data the extension handles and how.

Summary

FlagSwap does not collect, transmit, or sell any personal data. All configuration stays on your own device. There are no analytics, no trackers, and no third-party services.

What data FlagSwap stores

FlagSwap stores the following locally in your browser using the browser's storage API:

• Your feature-flag overrides (which flags you set on or off).
• Named flag groups you create.
• Per-domain and per-subdomain profiles.
• Per-container profiles (Firefox only): the container's identifier (for example firefox-container-3), the name and colour Firefox already displays for it, and the overrides you assign to it.
• Extension settings.
• Flags discovered on pages you visit. When a page you open evaluates LaunchDarkly flags, FlagSwap records each flag's key, its type (boolean, string, number, JSON) and its current value, so it can offer the right control for that flag without requiring a LaunchDarkly account. Nothing else about the page is recorded — no page content, no URLs, no browsing history — and this list, like everything else here, stays on your device.
• An optional LaunchDarkly REST API token that you choose to enter, used only for the optional flag-sync feature, and the flag definitions retrieved with it.

This data never leaves your device except as described under “Network activity” below. It is not sent to the developer or to any server we control. We have no access to it.

Network activity

• On the pages you visit: because LaunchDarkly-powered apps run on arbitrary hosts — localhost, staging subdomains, per-customer production domains — FlagSwap's content script is loaded on every page, and becomes active only on pages that actually evaluate LaunchDarkly flags. On those pages it reads and modifies the LaunchDarkly flag-evaluation traffic locally, in the page, so your configured values are used. On every other page it does nothing. In neither case is any page content, URL, or traffic sent to us or to anyone else.
• Optional flag sync: if you enter a LaunchDarkly API token, FlagSwap uses it to request your own flag definitions directly from LaunchDarkly's REST API — at app.launchdarkly.com, or at app.eu.launchdarkly.com / app.launchdarkly.us if you select the EU or US-federal region. This request goes only to LaunchDarkly, using your token, and is subject to LaunchDarkly's privacy policy. The token and the retrieved flag data are stored only in your browser.

Firefox containers

On Firefox, FlagSwap can scope overrides to a container (a “contextual identity”), so tabs on the same site in different containers can receive different flag values. This feature requires two Firefox permissions, and it is worth being precise about what they are used for:

• cookies — requested only because Firefox uses this permission to decide whether an extension may see which container a tab belongs to. FlagSwap never reads, writes, or transmits the contents of your cookies. It uses nothing from this permission but the container identifier.
• contextualIdentities — used to list your containers by their existing name and colour, so you can pick one when creating a container profile.

Determining which container the current tab belongs to is a message passed between FlagSwap's own components inside your browser. It involves no network request and no server. Container names and identifiers are stored locally with the rest of your configuration and are never transmitted.

The Chrome build of FlagSwap does not request either permission, and the container feature is inactive there.

How your data is used

Stored data is used solely to provide the extension's function: applying your flag overrides and remembering your groups, profiles, and settings between sessions. FlagSwap does not use your data for advertising, profiling, credit assessment, or any purpose unrelated to its single purpose.

Data sharing

FlagSwap does not share, transfer, or sell your data to anyone.

Data retention and removal

Data persists in your browser until you remove it — by clearing an override or profile within FlagSwap, or by uninstalling the extension, which deletes all of its stored data. You can remove a saved API token at any time from the extension's settings.

Children

FlagSwap is a developer tool and is not directed to children.

Changes to this policy

If this policy changes, the updated version will be posted at this URL with a new “Last updated” date.

Contact

Questions about this policy: flagswap@raufbabayev.com