What's New In DevTools (Chrome 68)

By Kayce Basques

Technical Writer, Chrome DevTools & Lighthouse

New to DevTools in Chrome 68:

• Eager Evaluation. As you type expressions, the Console previews the result.
• Argument hints. As you type functions, the Console shows you the expected arguments for that function.
• Function autocompletion. After typing a function call such as document.querySelector('p'), the Console shows you the functions and properties that the return value supports.
• ES2017 keywords in the Console. Keywords such as await are now available in the Console's autocomplete UI.
• Lighthouse 3.0 in the Audits panel. Faster, more consistent audits, a new UI, and new audits.
• BigInt support. Try out JavaScript's new arbitrary-precision integer in the Console.
• Adding property paths to the Watch pane. Add properties from the Scope pane to the Watch pane.
• "Show timestamps" moved to Settings.

Note: Check what version of Chrome you're running at chrome://version. If you're running an earlier version, these features won't exist. If you're running a later version, these features may have changed. Chrome auto-updates to a new major version about every 6 weeks.

Read on, or watch the video version of the release notes, below.

Assistive Console

Chrome 68 ships with a few new Console features related to autocompletion and previewing.

Eager Evaluation

When you type an expression in the Console, the Console can now show a preview of the result of that expression below your cursor.

Figure 1. The Console is printing the result of the sort() operation before it has been explicitly executed

To enable Eager Evaluation:

1. Open the Console.
2. Open Console Settings .
3. Enable the Eager evaluation checkbox.

DevTools does not eager evaluate if the expression causes side effects.

Argument hints

As you're typing out functions, the Console now shows you the arguments that the function expects.

Figure 2. Various examples of argument hints in the Console

Notes:

• A question mark before an arg, such as ?options, represents an optional arg.
• An ellipsis before an arg, such as ...items, represents a spread.
• Some functions, such as CSS.supports(), accept multiple argument signatures.

Autocomplete after function executions

Note: This feature depends on Eager Evaluation, which needs to be enabled from Console Settings .

After enabling Eager Evaluation, the Console now also shows you which properties and functions are available after you type out a function.

Figure 3. The top screenshot represents the old behavior, and the bottom screenshot represents the new behavior that supports function autocompletion

ES2017 keywords in autocomplete

ES2017 keywords, such as await, are now available in the Console's autocomplete UI.

Figure 4. The Console now suggests await in its autocomplete UI

Faster, more reliable audits, a new UI, and new audits

Chrome 68 ships with Lighthouse 3.0. The next sections are a roundup of some of the biggest changes. See Announcing Lighthouse 3.0 for the full story.

Faster, more reliable audits

Lighthouse 3.0 has a new internal auditing engine, codenamed Lantern, which completes your audits faster, and with less variance between runs.

New UI

Lighthouse 3.0 also brings a new UI, thanks to a collaboration between the Lighthouse and Chrome UX (Research & Design) teams.

Figure 5. The new report UI in Lighthouse 3.0

New audits

Lighthouse 3.0 also ships with 4 new audits:

• First Contentful Paint
• robots.txt is not valid
• Use video formats for animated content
• Avoid multiple, costly round trips to any origin

BigInt support

Note: This isn't a DevTools features per se, but it is a new JavaScript capability that you can try out in the Console.

Chrome 68 supports a new numeric primitive called BigInt. BigInt lets you represent integers with arbitrary precision. Try it out in the Console:

Figure 6. An example of BigInt in the Console

Add property path to watch

While paused on a breakpoint, right-click a property in the Scope pane and select Add property path to watch to add that property to the Watch pane.

Figure 7. An example of Add property path to watch

"Show timestamps" moved to settings

The Show timestamps checkbox previously in Console Settings has moved to Settings.

Feedback

Was this page helpful?

To discuss the new features and changes in this post, or anything else related to DevTools:

• File bug reports at Chromium Bugs.
• Discuss features and changes on the Mailing List. Please don't use the mailing list for support questions. Use Stack Overflow, instead.
• Get help on how to use DevTools on Stack Overflow. Please don't file bugs on Stack Overflow. Use Chromium Bugs, instead.
• Tweet us at @ChromeDevTools.
• File bugs on this doc in the Web Fundamentals repository.

Consider Canary

If you're on Mac or Windows, please consider using Chrome Canary as your default development browser. If you report a bug or a change that you don't like while it's still in Canary, the DevTools team can address your feedback significantly faster.

Note: Canary is the bleeding-edge version of Chrome. It's released as soon as its built, without testing. This means that Canary breaks from time-to-time, about once-a-month, and it's usually fixed within a day. You can go back to using Chrome Stable while Canary is broken.

Discover other DevTools features

Below is a list of everything that's been covered in the What's New In DevTools series.

Chrome 72

• 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.

Chrome 71

• 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.

Chrome 70

• 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.

Chrome 68

• 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.

Chrome 67

• 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.
• JavaScript VM instances clearly listed in the Memory panel.
• Network tab renamed to Page tab.
• Dark theme updates.
• Certificate transparency information in the Security panel.
• Site isolation features in the Performance panel.

Chrome 66

• 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.

Chrome 65

• 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.

Chrome 64

• Performance Monitor.
• Console Sidebar.
• Group similar Console messages.

Chrome 63

• Multi-client remote debugging support.
• Workspaces 2.0.
• 4 new audits.
• Simulate push notifications with custom data.
• Trigger background sync events with custom tags.

Chrome 62

• 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.

Chrome 61

• 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.

Chrome 60

• 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.

Chrome 59

• CSS and JS code coverage.
• Full-page screenshots.
• Block requests.
• Step over async await.
• Unified Command Menu.