DevScope – Developer Tools

Advanced developer tools for analyzing, inspecting, and debugging web pages directly in your browser.

DevScope is a professional browser development toolkit for on-demand inspection and diagnostics of the active webpage. Analyze page structure, CSS, performance, network activity, security headers, accessibility, SEO, storage, runtime behavior, and detected frameworks without switching between scattered tools. 🧩 DOM AND ELEMENT INSPECTION • Analyze DOM depth, complexity, duplicate IDs, detached nodes, inline styles, and semantic structure • Select elements directly on the page with highlight overlays and breadcrumb navigation • Review actionable hints for common structural anti-patterns 🎨 CSS INSPECTION AND LIVE EDITING • View computed styles, box model details, and the properties that actually apply • Detect specificity conflicts and possible layout issues • Edit styles live, see changes immediately, and reset individual properties ⚡ PERFORMANCE AND CORE WEB VITALS • Review Core Web Vitals, paint timing, resource timing, and long tasks • Inspect JavaScript execution signals and resource usage by type • Identify slow assets and likely performance bottlenecks 🌐 NETWORK, STORAGE AND RUNTIME • Group network requests by type and status and inspect timing details • Review LocalStorage, SessionStorage, cookies, IndexedDB, and Cache API data • Inspect runtime errors, console messages, event listeners, timers, and script activity 🔐 SECURITY AND ACCESSIBILITY • Validate HTTPS, mixed content, CSP, HSTS, Permissions-Policy, and X-Frame-Options • Run WCAG-oriented checks for ARIA, contrast, landmarks, labels, and missing alternative text • Use clear findings and recommendations to prioritize fixes 🔎 SEO AND FRAMEWORK DETECTION • Check meta tags, Open Graph, canonical URLs, structured data, heading hierarchy, and indexability • Detect React, Vue, Angular, Svelte, jQuery, Next.js, Nuxt.js, Tailwind CSS, Bootstrap, and other libraries • Review available version information and possible outdated dependencies 🏥 SITE HEALTH REPORT • Generate prioritized findings grouped as P0, P1, and P2 • Use the DX Score from 0 to 100 as a quick technical health indicator • Review stability, network, performance, and DOM-quality signals in one report 📊 EXPORT AND COMPARE • Export reports in JSON, CSV, or Markdown • Create snapshots and compare results to identify regressions • Export individual modules for focused review 🛠️ BUILT FOR REAL DEBUGGING Dock the panel on the right or bottom, use floating mode, resize it, and toggle it with Ctrl+Shift+D. Shadow DOM isolation helps reduce interference with inspected pages. Dark and light themes are available, with system synchronization where supported. The interface is available in 15 languages. 🔒 PRIVACY FIRST The extension does not collect personal data, track browsing activity, run analytics or telemetry, or contact external servers. Page analysis runs locally on the device. Preferences are stored in the browser and remain on the machine. 🏢 ABOUT THE AUTHOR DevScope is developed by POLPROG, a Polish technology company creating browser extensions, web applications, and mobile apps with a focus on privacy. Website: https://polprog.pl/ DevScope product page: https://polprog.pl/apps/DevScope/ Browser version: https://addons.mozilla.org/firefox/addon/devscope/