Little Rat bet users want to see what Chrome extensions send home; 555-pt HN

Little Rat is a small, open-source Chrome extension that shows the network calls made by other installed extensions and can optionally block them. It launched as a Show HN on 2023-08-14, when its developer described it as 'a small chrome extension to monitor (and optionally block) other extensions' network calls', and users initially installed it manually from GitHub because the Web Store submission was still in review.

The bet was that browser users want a watchdog: extensions phone home, inject trackers and break store policy, and the only way to check was auditing every extension by hand. Little Rat turned that into a one-click audit — a popup listing each extension's outbound calls — and added blocking for extensions users did not trust.

The launch thread drew 555 points and 101 comments and doubled as a support desk. Store review rejected the first submission on 2023-08-15 for an insufficient description; after reworking the listing and making the management and debug permissions optional, the developer won approval on 2023-08-18 for a version that can block but not count requests, because the debug API is undefined in the store build — so he kept two versions, a limited store one and the full manual one.

As of 2026-09-05 the repository is still live at 2.3k stars with 33 commits, but the README carries a new warning: a Chromium change now requires the extensions-on-chrome-urls flag to detect and block other extensions' traffic. The project remains a free tool by an individual — no company, funding or revenue is documented.