Privacy Policy — STZ Downloader (browser extension)
Last updated: 2026-06-28

STZ Downloader is an open-source download manager. The browser extension's only job is to hand downloads from your browser to the STZ Downloader application running locally on your own computer.

What the extension accesses
To send a download to the local app, the extension reads, for the file you are downloading:

The download URL.
The page referrer and the browser User-Agent.
Cookies for that URL — required so that downloads behind a login/session work (the same way the browser itself would authenticate the download).
It also stores a small local on/off setting using the browser's storage API.

Where the data goes
All of the above is sent only to the STZ Downloader application on your own machine. The extension uses the browser's Native Messaging API; the registered STZ helper forwards the request to an authenticated loopback connection on a dynamically selected local port.

The data is never sent to STZ Labs, the developer, or any third party.
There are no analytics, no tracking, and no remote servers.
Nothing is collected or stored by us. We have no servers that receive your data.
If the local application is not running, the extension simply does nothing and the browser downloads the file normally.

Permissions and why they are needed
Permission Why
downloads Detect a starting download and cancel it so the local app can take over.
cookies Pass your session cookies to the local app so authenticated downloads succeed.
<all_urls> (host) Downloads can originate from any site, so the extension must be able to read the request context on any site.
storage Save the local enabled toggle.
contextMenus Add the "Download with STZ Downloader" right-click item.
nativeMessaging Communicate with the installed STZ Downloader helper without relying on a fixed TCP port.
Data retention
The extension keeps no history. Cookies/URLs are read on the fly for each download and passed straight to the local app; they are not retained by the extension.

Contact
Questions or issues: https://github.com/starzynhobr/stz-downloader/issues