Complete installation context for the PoE2 live search snipe tool stack: 10 Mirrors (completely free and open-source Tampermonkey userscript) and 40 Mirrors (paid Windows OCR program).
The Installation page explains supported browsers (Chrome, Edge, Firefox, Brave), installing Tampermonkey or an equivalent userscript manager from official stores, adding the 10 Mirrors script to the trade site, and obtaining the 40 Mirrors installer. It references visual examples where the repository ships screenshots.
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Set up 10 Mirrors and 40 Mirrors using the paths that match each product.
Install Tampermonkey in your browser of choice, letting 10 Mirrors interact with the trade site. Chrome, Edge, and Brave users must enable custom user scripts in the browser settings:
Open the 10 Mirrors source page, copy the full script, then add it as a new script in Tampermonkey:

Load any page on the official Path of Exile trade site. With Tampermonkey and 10 Mirrors active, the in-page interface should appear. You can drag it to reposition it as needed.

Complete your donation on Gumroad. You will receive access to downloads and a license key for 40 Mirrors.
If the UI does not appear, double-check that the script is enabled on the Tampermonkey dashboard. Next, navigate to the trade site and click the Tampermonkey icon in your browser's toolbar. Verify that 10 Mirrors is toggled on.