Worked on the getsentry/spotlight repository to resolve a routing path stacking issue affecting the Sidebar and Detail Tabs in the telemetry UI. Addressed the problem by migrating navigation from relative to absolute paths, introducing a centralized TELEMETRY_BASE_URL constant, and upgrading to React Router DOM v7.17.0. Refactored navigation logic across components to ensure stable deep-link navigation and removed legacy root overrides for consistency. Added comprehensive regression tests using TypeScript to maintain type safety and prevent future issues. Manual QA confirmed the fix, resulting in improved code health and reduced regressions. Utilized React, JavaScript, and front end testing throughout the process.