The main goal of this thesis is to design and implement a mechanism that provides protection against stateless tracking with browser fingerprint. Implemented tool has a form of module that takes part of JavaScript Restrictor extension. The module allows to specify heuristics used for evaluation of visited sites that may contain browser fingerprint extraction. If suspicious activity is detected, all subsequent HTTP requests from that site are blocked to prevent the extracted fingerprint from being sent to the server. The implementation and defined heuristics were tested. The resulting module represents an effective tool against stateless tracking. The main limitation of the implementation is possible corruption of sites by blocking HTTP requests.

The aim of the thesis was to design, implement and evaluate the results of automatic tests for the JavaScript Restrictor project, which is being developed as a web browser extension. The tests are divided into three levels - unit, integration, and system. The Unit Tests verify the behavior of individual features, the Integration Tests verify the correct wrapping of browser API endpoints, and the System Tests check that the extension does not suppress the desired functionality of web pages. The System Tests are implemented for parallel execution in a distributed environment which has succeeded in achieving an almost directly proportional reduction in time with respect to the number of the tested nodes. The benefit of this work is detection of previously unknown errors in the JavaScript Restrictor extension and provision of the necessary information that allowed to fix some of the detected bugs.