What's New In DevTools (Chrome 67)

Published on Wednesday, April 11, 2018

Kayce Basques

Technically, I'm a writer

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New features and major changes coming to DevTools in Chrome 67 include:

Search across all network headers
CSS variable value previews in the Styles pane
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
The Network tab in the Sources panel has been renamed to the Page tab
Dark theme updates
Certificate transparency information in the Security panel
Site isolation features in the Performance panel

Video version of the release notes:

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.

Search across all network headers and responses

Open the Network panel then press Command+F (Mac) or Control+F (Windows, Linux, ChromeOS) to open the new Network Search pane. DevTools searches the headers and bodies of all network requests for the query that you provide.

Figure 1. Searching for the text cache-control with the new Network Search pane

Click Match Case to make your query case-sensitive. Click Use Regular Expression to show any results that match the pattern you provide. You don't need to wrap your RegEx in forward slashes.

Figure 2. A regular expression query in the Network Search pane.

Search pane UI updates

The UI of the Global Search pane now matches the UI of the new Network Search pane. It now also pretty-prints results to aid scannability.

Figure 3. The old UI on the left, and the new UI on the right

Press Command+Option+F (Mac) or Control+Shift+F (Windows, Linux, ChromeOS) to open Global Search. You can also open it via the Command Menu.

CSS variable value previews in the Styles pane

When the value of a CSS color property, such as background-color or color, is set to a CSS variable, DevTools now shows a preview of that color.

An example of CSS variable color values.

Figure 4. In the old UI on the left, there is no color preview next to color: var(--main-color), whereas in the new UI on the right, there is

Copy as fetch

Right-click a network request then select Copy > Copy As Fetch to copy the fetch()-equivalent code for that request to your clipboard.

Figure 5. Copying the fetch()-equivalent code for a request

DevTools produces code like the following:

fetch("https://preload.glitch.me/styles.css", {
  "credentials": "omit",
  "headers": {},
  "referrer": "https://preload.glitch.me/after/",
  "referrerPolicy": "no-referrer-when-downgrade",
  "body": null,
  "method": "GET",
  "mode": "cors"
});

Audits panel updates

New audits

The Audits panel has 2 new audits, including:

Preload key requests. Preloading requests can speed up page load time by giving hints to the browser to download resources that are important for your Critical Rendering Path as soon as possible.
Avoid invisible text while webfonts are loading. Ensuring that text is visible while webfonts load makes the page more useful to users faster.

New configuration options

You can now configure the Audits panel to:

Preserve desktop viewport and user agent settings. In other words, you can prevent the Audits panel from simulating a mobile device.
Disable network and CPU throttling.
Preserve storage, such as LocalStorage and IndexedDB, across audits.

Figure 6. New audit configuration options

View traces

After auditing a page, click View Trace to view the load performance data that your audit is based off of in the Performance panel.

Figure 7. The View Trace button

Stop infinite loops

If you work with for loops, do...while loops, or recursion a lot, you've probably executed an infinite loop by mistake while developing your site. To stop the infinite loop, you can now:

Open the Sources panel.
Click Pause . The button changes to Resume Script Execution .
Hold Resume Script Execution then select Stop Current JavaScript Call .

In the video above, the clock is being updated via a setInterval() timer. Clicking Start Infinite Loop runs a do...while loop that never stops. The interval resumes because it wasn't running when Stop Current JavaScript Call Stop was selected.

User Timing in the Performance tabs

When viewing a Performance recording, click the User Timing section to view User Timing measures in the Summary, Bottom-Up, Call Tree and Event Log tabs.

Figure 8. Viewing User Timing measures in the Bottom-Up tab. The blue bar to the left of the User Timing section indicates that it is selected.

In general, you can now select any of the sections (Main Thread, User Timing, GPU, ScriptStreamer, and so on) and view that section's activity in the tabs.

Select JavaScript VM instances in the Memory panel

The Memory panel now clearly lists out all JavaScript VM instances associated with a page, rather than hiding them behind the Target dropdown menu as before.

Before and after screenshots of the Memory panel.

Figure 9. In the old UI on the left, the JavaScript VM instances are hidden behind the Target dropdown menu, whereas in the new UI on the right they are shown in the Select JavaScript VM Instance table

Next to the developers.google.com instance there are 2 values: 8.7 MB and 13.3 MB. The left value represents memory allocated because of JavaScript. The right value represents all OS memory that is being allocated because of that VM instance. The right value is inclusive of the left value. In Chrome's Task Manager, the left value corresponds to JavaScript Memory and the right value corresponds to Memory Footprint.

Network tab renamed to Page tab

On the Sources panel, the Network tab is now called the Page tab.

Two DevTools windows side-by-side, demonstrating the name change.

Figure 10. In the old UI on the left, the tab showing the page's resources is called Network, whereas in the new UI on the right it's called Page

Dark theme updates

Chrome 67 ships with a number of minor changes to the dark theme color scheme. For example, the breakpoint icons and the current line of execution are now green.

Figure 11. A screenshot of the new breakpoint icon and current line of execution color scheme

Certificate transparency in the Security panel

The Security panel now reports certificate transparency information.

Certificate transparency information in the Security panel.

Figure 12. Certification transparency information in the Security panel

Site Isolation in the Performance panel

If you've got Site Isolation enabled, the Performance panel now provides a flame chart for each process so that you can see the total work that each process is causing.

Figure 13. Per-process flame charts in a Performance recording

Download the preview channels

Consider using the Chrome Canary, Dev or Beta as your default development browser. These preview channels give you access to the latest DevTools features, test cutting-edge web platform APIs, and find issues on your site before your users do!

Getting in touch with the Chrome DevTools team

Use the following options to discuss the new features and changes in the post, or anything else related to DevTools.

Submit a suggestion or feedback to us via crbug.com.
Report a DevTools issue using the More options > Help > Report a DevTools issues in DevTools.
Tweet at @ChromeDevTools.
Leave comments on our What's new in DevTools YouTube videos.