The matre$ka project is a fork of the Firefox for Android browser based on Fenix 160.0a1. It introduces a patch for GeckoView that enables limited support for Russian Trusted certificate chains, allowing the browser to validate websites that were previously inaccessible due to TLS certificate issues.
The implementation includes two built-in Russian root certificates. The browser validates certificate chains against these roots for specific hosts. A fallback mechanism is enabled by default for domains ending in .ru and .рф, allowing them to be verified even if they are not explicitly listed in the configuration.
The developer notes that this solution does not prevent man-in-the-middle attacks. Adding new trust anchors expands the browser's trust model, and the project is not intended to be a security recommendation for financial transactions. Root certificates are bundled within the APK and can only be updated by installing a new version of the application.
The project supports Android 8+ on arm64-v8a architecture. Source code, build instructions, and APK files are available in the repository, with the developer emphasizing the need for independent code audits and verification of the build process to ensure security.