Privacy policy

Updated on 12 November 2026, for version 1.0.0.

Uncommon is a browser extension that runs a Wikimedia editor's userscripts and stylesheets from a copy kept in the browser, in place of their common.js. This policy covers the extension as published in the Chrome Web Store, Firefox Add-ons and Microsoft Edge Add-ons.

In short

Uncommon collects nothing. What it stores stays in your browser, and the only requests it makes are anonymous queries to the Wikimedia wikis your scripts come from. It has no analytics, no tracking and no advertising, and its author receives no data from it.

What Uncommon stores in your browser

Everything below is kept in the extension's own storage on your device:

• your settings: the language of its pages, whether it is paused, and how often it checks the wikis;
• your profiles: the username and the home wiki of each wiki account you add;
• your records: the wiki pages you added, their approved, previous and waiting revisions (number, date, author, edit summary, size and checksum) with their texts, your drafts, and each record's settings;
• the reports of the last 200 wiki page loads on which a profile's scripts were due: the address and title of the page, the username the wiki gave, and when each script ran, why it was skipped, or the error it threw;
• the report of the page open in each tab, until the browser closes.

What Uncommon sends, and to whom

Uncommon sends requests only to the Action API (/w/api.php) of the Wikimedia wikis your records come from. It asks for the pages you added and their latest revisions, for the gadgets of your home wiki when you add one, and for your common.js, global.js or their stylesheets when you import them. The requests carry no cookies and no login: only the titles or revision numbers asked for, and a User-Agent that names Uncommon, its version and this site. What the wikis do with requests is covered by the Wikimedia Foundation's privacy policy.

Uncommon sends nothing to its author or to anyone else, and it doesn't sell, share or transfer data.

The scripts you run

The scripts you add are code written by you or by other editors. They run in the wiki's pages under your account, as they would from your common.js, and what they do is up to them. Only User: subpages and MediaWiki: pages can be added, which only their owner or the wiki's administrators can edit, and a revision saved by another editor runs only once you have approved it.

Why it asks for each permission

• User scripts: to run the scripts you added.
• Storage: to keep what is listed above.
• Alarms: to check the wikis for new revisions at the interval you set.
• Scripting: to receive each page's report of which scripts ran, on the wikis you allowed.
• Access to a wiki: asked for one Wikimedia wiki at a time, when one of your scripts first runs there.

Removing your data

The Activity page clears the reports, and Settings removes a profile with its records. Uninstalling the extension removes everything it stored. To keep a copy first, export the state file in Settings.

Changes

This page describes the current version. A version that changes what is stored or sent comes with an updated policy here, with its date above.

Contact

Questions go to User talk:Fenakhay on Meta-Wiki.