Worked on stability and code quality improvements across JetBrainsRuntime and openjdk/jfx repositories, focusing on Java-based testing and maintainability. Addressed environment-specific test instability in JetBrainsRuntime by updating the cross-platform AWT/Swing test exclusion list, which reduced flaky test failures and improved CI reliability. In openjdk/jfx, introduced a package declaration to GifImageTestApp, replacing the default package to enhance code organization and align with project conventions. Employed Java, Git, and software testing skills throughout, with all changes undergoing code review and integration. The work emphasized targeted bug fixing, code clarity, and adherence to best practices in cross-platform Java development environments.