Copy element's styles
Right-click a node in the DOM Tree to copy that DOM node's CSS to your clipboard.
Visualize layout shifts
Supposing you're reading a news article on your favorite website. As you're reading the page, you keep losing your place because the content is jumping around. This problem is called layout shifting. It usually happens when images and ads finish loading. The page hasn't reserved any space for the images and ads, so the browser has to shift all the other content down to make room for them. The solution is to use placeholders.
DevTools can now help you detect layout shifting:
- Open the Command Menu.
- Start typing
- Run the Show Rendering command.
- Enable the Layout Shift Regions checkbox. As you interact with a page, layout shifts are highlighted blue.
Lighthouse 5.1 in the Audits panel
The Audits panel is now running Lighthouse 5.1. New audits include:
- Provides a valid
apple-touch-icon. Checks that a PWA can be added to an iOS homescreen.
- Keep request counts and file sizes low. Reports the total number of network requests and file sizes for various categories, such as documents, scripts, stylesheets, images, and so on.
- Maximum Potential First Input Delay. Measures the maximum potential time between a user's first page interaction and the browser's response to that interaction. Note that this metric replaces the Estimated Input Latency metric. Maximum Potential First Input Delay does not factor into your Performance category score.
The Node and CLI versions of Lighthouse 5.1 have 3 new major features worth checking out:
- Performance Budgets. Prevent your site from regressing over time by specifying request counts and file sizes that pages should not exceed.
- Plugins. Extend Lighthouse with your own custom audits.
- Stack Packs. Add audits tailored to specific technology stacks. The WordPress Stack Pack shipped first. React and AMP Stack Packs are in development.
OS theme syncing
If you're using the dark theme of your OS, DevTools now switches to its own dark theme automatically.
Keyboard shortcut for opening the Breakpoint Editor
Prefetch cache in Network panel
The Size column of the Network panel now says
(prefetch cache) when a resource was loaded from
the prefetch cache. Prefetch is a new-ish web platform feature for speeding up subsequent
page loads. Can I use... reports that it's supported in 83.33% of global browsers as of July 2019.
See Prefetch Demo to try it out.
Private properties when viewing objects
The Console now shows private class fields in its object previews.
Notifications and push messages in the Application panel
The Background Services section of the Application panel now supports Push Messages and Notifications. Push Messages occur when a server sends information to a service worker. Notifications occur when a service worker or page script shows information to the user.
As with the Background Fetch and Background Sync features from Chrome 76, once you start recording, Push Messages and Notifications on this page are recorded for 3 days, even when the page is closed, and even when Chrome is closed.
To discuss the new features and changes in this post, or anything else related to DevTools:
- File definite bug reports and feature requests at Chromium Bugs.
- Discuss possible features, changes, and bugs on the Mailing List.
- Get help on how to use DevTools on Stack Overflow.
- Tweet us at @ChromeDevTools.
- File bugs on this document in the Web Fundamentals repository.
If you're on Mac or Windows, consider using Chrome Canary as your default development browser. Canary gives you access to the latest DevTools features.
Discover other DevTools features
Below is a list of everything that's been covered in the What's New In DevTools series.
- Support for
classredeclarations in the Console
- Improved WebAssembly debugging
- Request Initiator Chains in the Initiator tab
- Highlight the selected network request in the Overview
- URL and path columns in the Network panel
- Updated User-Agent strings
- New Audits panel configuration UI
- Per-function or per-block code coverage modes
- Code coverage must now be initiated by a page reload
- Debug why a cookie was blocked
- View cookie values
- Simulate different prefers-color-scheme and prefers-reduced-motion preferences
- Code coverage updates
- Debug why a network resource was requested
- Console and Sources panels respect indentation preferences again
- New shortcuts for cursor navigation
- Multi-client support in the Audits panel
- Payment Handler debugging
- Lighthouse 5.2 in the Audits panel
- Largest Contentful Paint in the Performance panel
- File DevTools issues from the Main Menu
- Copy element styles
- Visualize layout shifts
- Lighthouse 5.1 in the Audits panel
- OS theme syncing
- Keyboard shortcut for opening the Breakpoint Editor
- Prefetch cache in the Network panel
- Private properties when viewing objects
- Notifications and push messages in the Application panel
- Autocomplete with CSS values
- A new UI for network settings
- WebSocket messages in HAR exports
- HAR import and export buttons
- Real-time memory usage
- Service worker registration port numbers
- Inspect Background Fetch and Background Sync events
- Puppeteer for Firefox
- Meaningful presets when autocompleting CSS functions
- Clear site data from the Command Menu
- View all IndexedDB databases
- View a resource's uncompressed size on hover
- Inline breakpoints in the Breakpoints pane
- IndexedDB and Cache resource counts
- Setting for disabling the detailed Inspect tooltip
- Setting for toggling tab indentation in the Editor
- Highlight all nodes affected by CSS property
- Lighthouse v4 in the Audits panel
- WebSocket binary message viewer
- Capture area screenshot in the Command Menu
- Service worker filters in the Network panel
- Performance panel updates
- Long tasks in Performance panel recordings
- First Paint in the Timing section
- Bonus tip: Shortcut for viewing RGB and HSL color codes (video)
- Detailed tooltips in Inspect Mode
- Export code coverage data
- Navigate the Console with a keyboard
- AAA contrast ratio line in the Color Picker
- Save custom geolocation overrides
- Code folding
- Frames tab renamed to Messages tab
- Bonus tip: Network panel filtering by property (video)
- Visualize performance metrics in the Performance panel
- Highlight text nodes in the DOM Tree
- Copy the JS path to a DOM node
- Audits panel updates, including a new audit that detects JS libraries and new keywords for accessing the Audits panel from the Command Menu
- Bonus tip: Use Device Mode to inspect media queries (video)
- Hover over a Live Expression result to highlight a DOM node
- Store DOM nodes as global variables
- Initiator and priority information now in HAR imports and exports
- Access the Command Menu from the Main Menu
- Picture-in-Picture breakpoints
- Bonus tip: Use
monitorEvents()to log a node's fired events in the Console (video)
- Live Expressions in the Console
- Highlight DOM nodes during Eager Evaluation
- Performance panel optimizations
- More reliable debugging
- Enable network throttling from the Command Menu
- Autocomplete Conditional Breakpoints
- Break on AudioContext events
- Debug Node.js apps with ndb
- Bonus tip: Measure real world user interactions with the User Timing API
- Eager Evaluation
- Argument hints
- Function autocompletion
- ES2017 keywords
- Lighthouse 3.0 in the Audits panel
- BigInt support
- Adding property paths to the Watch pane
- "Show timestamps" moved to Settings
- Bonus tip: Lesser-known Console methods (video)
- Search across all network headers
- CSS variable value previews
- Copy as fetch
- New audits, desktop configuration options, and viewing traces
- Stop infinite loops
- User Timing in the Performance tabs
- Network tab renamed to Page tab
- Dark theme updates
- Certificate transparency information in the Security panel
- Site isolation features in the Performance panel
- Bonus tip: Layers panel + Animations Inspector (video)
- Blackboxing in the Network panel
- Auto-adjust zooming in Device Mode
- Pretty-printing in the Preview and Response tabs
- Previewing HTML content in the Preview tab
- Local Overrides support for styles inside of HTML
- Bonus tip: Blackbox framework scripts to make Event Listener Breakpoints more useful
- Local Overrides
- New accessibility tools
- The Changes tab
- New SEO and performance audits
- Multiple recordings in the Performance panel
- Reliable code stepping with workers in async code
- Bonus tip: Automate DevTools actions with Puppeteer (video)
- Performance Monitor
- Console Sidebar
- Group similar Console messages
- Bonus tip: Toggle hover pseudo-class (video)
- Multi-client remote debugging support
- Workspaces 2.0
- 4 new audits
- Simulate push notifications with custom data
- Trigger background sync events with custom tags
- Bonus tip: Event listener breakpoints (video)
- Top-level await in the Console
- New screenshot workflows
- CSS Grid highlighting
- A new Console API for querying objects
- New Console filters
- HAR imports in the Network panel
- Previewable cache resources
- More predictable cache debugging
- Block-level code coverage
- Mobile device throttling simulation
- View storage usage
- View when a service worker cached responses
- Enable the FPS meter from the Command Menu
- Set mousewheel behavior to zoom or scroll
- Debugging support for ES6 modules
- New Audits panel
- 3rd-Party Badges
- A new gesture for Continue To Here
- Step into async
- More informative object previews in the Console
- More informative context selection in the Console
- Real-time updates in the Coverage tab
- Simpler network throttling options
- Async stacks on by default
- CSS and JS code coverage
- Full-page screenshots
- Block requests
- Step over async await
- Unified Command Menu