Browser & OS extension stores

Browser extension stores reach end users directly rather than through a business admin, which makes them uniquely suited to consumer and prosumer products — ad blockers, password managers, writing aids, and productivity overlays. The same Chromium extension package usually ships to both Chrome and Edge with only minor manifest changes, so cross-store distribution is cheap.

The integration model is the browser extension itself: content scripts, background service workers, and browser-action UI built on Manifest V3. There is no marketplace-wide API rate limit — you are bound by whatever web APIs your extension calls — and auth is often minimal, though extensions can use OAuth for identity when they talk to a backend.

Review here centers on permissions and user-data handling. Chrome and Edge run automated plus manual policy review; Firefox emphasizes open code and data transparency. Because extensions run in a privileged context, over-broad permissions are the most common cause of rejection, so scope requests tightly.