Configuration is not evidence. The leak test asks the page.
The leak test opens the profile for real and asks its own page what a site can see: the address it reaches, what WebRTC hands out, the clock, the language and the position. Then it compares each with what the profile should show.
Mosaic is a desktop app
Email yourself the link and open it on your computer.
Leak test, step by step
Launch for real
The profile starts in its own browser, with its proxy and fingerprint, exactly as a site would meet it.
Ask the page
A probe in the page looks up the address it reaches over HTTPS, gathers the WebRTC candidates, and reads the timezone, language and position the page is given.
Compare
Each reading is set against what the profile is meant to show. A mismatch is a fail, with the two values side by side.
The smaller things it does
From the window, the companion or the API
Run it from the profile’s menu, from the companion inside its browser, or through the REST API and MCP.
A skip is not a pass
If the page never asked for a position, the geolocation row says skipped, not passed.
A clean leak test says nothing leaked on that run. It is not a verdict from any site, and it does not promise one.
Works with
Test a profile the way a site would, before a site does
A leak test and 49 public detectors, read for you.
Checked before every launchA profile does not open until its proxy has answered
No profile opens behind a proxy that has not answered.
Matched to the exitTimezone, language and location come from where the proxy comes out
Timezone, language and location follow the proxy.
Leak test is in every plan
Free holds 3 profiles and 10 profile creations, with the same engine as Pro. Pro is $49 a month for any number.
Mosaic is a desktop app
Email yourself the link and open it on your computer.