Developed headless mode support for TestDialogManager within the JetBrains/intellij-community repository, focusing on enhancing automated testing workflows. The work involved enabling TestDialogManager.setTestDialog to function in headless environments, aligning its behavior with MessagesServiceImpl.isApplicationInUnitTestOrHeadless to ensure consistent test execution across different modes. By reducing dependencies on GUI components, this update improved the reliability and throughput of continuous integration pipelines, allowing dialog tests to run automatically without manual intervention. The implementation leveraged Java and unit testing practices, emphasizing cross-module consistency and maintainability. This contribution addressed internal testing infrastructure, streamlining development cycles and supporting robust software development processes.