Experimental features

Microsoft Edge DevTools provide access to experimental features that are still in development. This article lists and describes the experimental features that are in either:

  • The latest version of the Canary preview channel of Microsoft Edge.
  • The latest version of the Stable release of Microsoft Edge.

All channels of Microsoft Edge have experimental features. You can get the latest experimental features by using the Microsoft Edge Canary channel. To view the full list available in your version of Microsoft Edge, see the Settings > Experiments page in DevTools.

These experiments could be unstable or unreliable and may require you to restart DevTools.

Experiments which are turned on by default

The following experimental features are turned on by default. You can use these features right away, without changing any settings. You can turn off these default experimental features, if needed.

Turned on by default in Microsoft Edge Canary v106:

Turned on by default in Microsoft Edge Stable v104:

Turning an experiment on or off

Experimental features are constantly being updated and might cause performance issues. This is one reason you might want to turn off an experiment.

To turn an experiment on or off in Microsoft Edge:

  1. To open DevTools, right-click the webpage, and then select Inspect. Or, press Ctrl+Shift+I (Windows, Linux) or Command+Option+I (macOS). DevTools opens.

  2. In DevTools, on the main toolbar, click the Settings (Settings icon.) button. Or, press Shift+?.

  3. On the left side of the Settings panel, select the Experiments page.

    The Experiments page in Settings.

  4. On the Experiments page, select or clear the checkbox for an experiment. Some experiments are turned on (selected) by default.

  5. Click Close (The Close icon in DevTools > Settings.) in the upper right to close DevTools Settings.

  6. Click the Reload DevTools button.

Restoring defaults for which experiments are selected

To restore the default settings for which experimental features are turned on:

  1. To open DevTools, right-click the webpage, and then select Inspect. Or, press Ctrl+Shift+I (Windows, Linux) or Command+Option+I (macOS). DevTools opens.

  2. In DevTools, on the main toolbar, click the Settings (Settings icon.) button. Or, press Shift+?. The Settings panel opens, with the Preferences page selected.

  3. At the bottom of the Preferences page, click the Restore defaults and refresh button, and then click Close (The Close icon in DevTools > Settings.).

Filtering the experiments

You can filter the experimental features by text included in the title.

  1. To open DevTools, right-click the webpage, and then select Inspect. Or, press Ctrl+Shift+I (Windows, Linux) or Command+Option+I (macOS). DevTools opens.

  2. In DevTools, on the main toolbar, click the Settings (Settings icon.) button. Or, press Shift+?. The Settings panel opens, with the Preferences page selected.

  3. On the left side of the Settings panel, select the Experiments page.

  4. Click in the Filter text box and enter text, such as timeline. As you type, only the matching checkboxes are shown in the Experiments page.

  5. To end filtering, clear the Filter text box.

Providing feedback about the experiments

We're eager to hear your feedback about experimental features. To share feedback with us, Contact the Microsoft Edge DevTools team.

One of the UI experiments adds a new way to provide feedback: when the Focus Mode experiment is turned on, at the bottom of the Activity Bar, select Help (the Help icon in the Activity Bar in Focus Mode.) > Feedback.

List of experiments

The experiments checkboxes that appear in the latest version of the Canary preview channel of Microsoft Edge are listed below. The Stable release is also noted, following behind the addition or removal of checkboxes in Canary.

Allow extensions to load custom stylesheets

Some Microsoft Edge Add-ons can define custom color themes for DevTools. If you install an add-on with a theme, you need to enable the Allow extensions to load custom stylesheets experiment to view the add-on themes.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Capture node creation stacks

To capture JavaScript stack traces when DOM nodes are added to the DOM at runtime, enable this experiment. The captured stack traces are displayed in the Stack Trace pane of the Elements panel.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Automatically pretty print in the Sources Panel

When this experiment is turned on, when you display a minified file in the Sources panel, the file is opened in a single tab in the Sources panel, pretty-printed.

When this experiment is turned off, a UI prompt with a button asks you whether to pretty-print the file. The file is opened in an additional tab which has an appended suffix of :formatted.

  • A minified file is concatenated into a single long line.
  • In contrast, pretty print presents the contents of a file in an indented, more human-readable format.

Status:

Protocol Monitor

DevTools communicates with the inspected page using the DevTools protocol.

To monitor the messages sent and received by DevTools to debug the inspected page:

  1. To open DevTools, right-click the webpage, and then select Inspect. Or, press Ctrl+Shift+I (Windows, Linux) or Command+Option+I (macOS). DevTools opens.

  2. In DevTools, on the main toolbar, click the Settings (Settings icon.) button. Or, press Shift+?. The Settings panel opens, with the Preferences page selected.

  3. On the left side of the Settings panel, select the Experiments page.

  4. Select the Protocol Monitor checkbox, and then click Close (The Close icon in DevTools > Settings.) to close Settings.

  5. Open the Command Menu (Ctrl+Shift+P), and then type protocol in the text box.

  6. Select Show Protocol monitor. The message appears: "One or more settings have changed which requires a reload to take effect."

  7. Click the Reload DevTools button that appears next to the message.

  8. The Protocol monitor tool is displayed in the Drawer at the bottom of DevTools.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Show CSP Violations view

Adds the CSP Violations tool, which displays any Content Security Policy (CSP) violations that are detected on the inspected webpage.

The CSP Violations tool.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Record coverage while performance tracing

Records coverage while performance tracing.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Show option to expose internals in heap snapshots

new as of v105

Whether to display a checkbox to expose internals in heap snapshots in the Memory tool.

See also:

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Source order viewer

This checkbox is being removed. The Source Order Viewer is not an experiment any longer. Whether the checkbox is checked or unchecked makes no difference; the Source Order Viewer feature appears in DevTools either way.

See also:

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Timeline: event initiators

Whether to include event initiators in the Timeline.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Timeline: WebGL-based flamechart

Whether to use a WebGL-based flamechart in the Timeline.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

WebAssembly Debugging: Enable DWARF support

Enables DWARF support for WebAssembly debugging. See Improved WebAssembly debugging in What's new in DevTools (Microsoft Edge 80).

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Console: Resolve variable names in expressions using source maps

Uses source maps to automatically map original variable names to minified variable names when evaluating expressions in the Console.

See Map the processed code to your original source code, for debugging.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Emulation: Support dual screen mode

new as of v106

Whether to show the UI to emulate dual-screen mode in device emulation.

See Emulate dual-screen and foldable devices.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is not present in Microsoft Edge Stable v104.

Enable new Advanced Perceptual Contrast Algorithm (APCA) replacing previous contrast ratio and AA/AAA guidelines

The Advanced Perceptual Contrast Algorithm (APCA) replaces the AA/AAA guidelines contrast ratio in the Color Picker. The Color Picker is used in the Styles tab in the Elements tool.

APCA is a new way to compute contrast. It is based on modern research on color perception. Compared to AA/AAA guidelines, APCA is more context-dependent. The contrast is calculated based on the following spatial properties of the text, color, and context.

  • Spatial properties of text that include font weight and size.
  • Spatial properties of color that include perceived contrast between text and background.
  • Spatial properties of context that include ambient light, surroundings, and intended purpose.

See also:

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Enable full accessibility tree view in the Elements panel

Adds a button in the Elements tool which toggles between the DOM tree and the accessibility tree.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Enable the Font Editor tool within the Styles pane

You can use the visual Font Editor to edit fonts. Use it define fonts and font characteristics. The visual Font Editor helps you do the following:

  • Switch between units for different font properties
  • Switch between keywords for different font properties
  • Convert units
  • Generate accurate CSS code

To use the visual Font Editor:

  1. To open DevTools, right-click the webpage, and then select Inspect. Or, press Ctrl+Shift+I (Windows, Linux) or Command+Option+I (macOS). DevTools opens.

  2. In DevTools, on the main toolbar, select the Elements tab. If the Elements tab isn't visible, click the More tabs (More tabs icon.) button, or else the More Tools (More Tools icon.) button.

  3. In the Styles tab, select the Font Editor icon.

    The visual Font Editor pane is highlighted.

For more information about the visual Font Editor, see Edit CSS font styles and settings in the Styles pane.

For more information, see Edit CSS font styles and settings in the Styles pane.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Enable automatic contrast issue reporting via the Issues Panel

Enables automatic contrast issue reporting in the Issues tool.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Enables experimental cookie features.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Enable Reporting API panel in the Application panel

Use the Reporting API to catch certain errors such as security violations or deprecated API calls. These errors happen when users visit your site and are sent to a server endpoint. Enable this experiment to add the Reporting API section in the Application panel, which lists all of the reports sent to the endpoint.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Display more precise changes in the Changes tab

See More precise changes in the Changes tab.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Sync CSS changes in the Styles pane

Whether to sync CSS changes in the Styles tab in the Elements tool.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Local overrides for response headers

Whether to use local overrides for response headers.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Enable CSS Authoring hints for inactive rules, deprecated properties, etc.

new as of v105

Whether to enable CSS authoring hints in the Styles panel of the Elements tool to display information tooltips next to inactive or deprecated properties.

This feature provides help when writing or inspecting CSS in the Styles panel. Small information icons appear next to CSS properties that are inactive or deprecated. An inactive property is one that applies correctly to an element but has no effect on it (for example, width:100px applied to an inline element has no effect).

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is not present in Microsoft Edge Stable v104.

Use Lighthouse panel with timespan and snapshot modes

Adds a selector to the Lighthouse tool to switch between different reporting modes. At the moment, the Navigation and Snapshot modes are supported.

See also:

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Tooling for CSS layers in the Styles pane

Adds increased support for the @layer CSS rule in the Styles pane. CSS rules in the Styles pane are grouped by the layers they belong to. A layer overview widget is displayed, which shows the layer tree for the currently inspected element.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Enable color picking outside the browser window

Allows you to move the mouse cursor when it's an eyedropper tool, over anywhere on your screen, not just within the Microsoft Edge window.

In the Elements tool, in the Styles tab, click on any color preview. The Color Picker opens. Click the Toggle color picker (Eyedropper icon button.) button. The mouse cursor becomes an eyedropper. Click anywhere on your monitor to select a color.

See also:

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Group sources into Authored and Deployed trees

new as of v104

Controls whether to group resources into separate Authored and Deployed trees in the Page tab of the Sources tool. This feature in the Sources tool allows you to group source files in two folders depending on whether these are:

  • Original source files (authored, that is, files with your local edits).
  • Production files (deployed files that are on the web server after compiling and bundling the source files).

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Hide ignore-listed code in sources tree view

new as of v106

Whether to hide or display code that's in the ignore list, in the Sources tool's tree view, such as the Page tab.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is not present in Microsoft Edge Stable v104.

Log DevTools uncaught exceptions to Console

Controls whether to log DevTools uncaught exceptions in the Console tool.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Enable webhint

webhint is an open-source tool that provides real-time feedback for websites and local webpages. The type of feedback provided by webhint includes:

  • Accessibility
  • Cross-browser compatibility
  • Security
  • Performance
  • Progressive Web Apps (PWAs)
  • Other common web development issues

The webhint experiment displays the webhint feedback in the Issues panel. Select an issue to display documentation about the solution and a list of the affected resources on your website. Select a resource link to open the relevant Network, Sources, or Elements pane in DevTools.

webhint feedback in the Issues panel.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Show issues in Elements

Enable this experiment to view syntax errors under HTML in the DOM view of the Elements tool. For more information, see Wavy underlines highlight code issues and improvements in Elements tool.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Focus Mode

Focus Mode is a new user interface for DevTools. Focus Mode is designed to simplify and streamline the DevTools UI, without compromising its feature set.

Focus Mode replaces the main row of tabs with an Activity Bar, which is a compact toolbar with distinctive icons. The Activity Bar makes it possible to pin, rearrange, and open your favorite tools, for quick access. The Activity Bar also provides access to user settings, help, and other features.

Focus Mode also provides a Quick View list, to open a second tool alongside the tool that's already selected in the Activity Bar.

See Reduce the complexity of DevTools with Focus Mode.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Open source files in Visual Studio Code

The Open source files in Visual Studio Code experiment replaces the code editor of the Sources tool with Visual Studio Code, for editing local files. When you turn on this experiment, Developer Tools detects when you edit a local file, and prompts you to select a folder to use as your Workspace.

When you select a folder to use as your Workspace, selecting any link to a file in DevTools opens the file in Visual Studio Code. In previous versions of Microsoft Edge, this action opened the file in the code editor of the Sources tool in DevTools.

Selecting a file link in the Styles tool opens the file in Visual Studio Code.

Any edits that you make in DevTools now change the file on the hard drive and sync live with Visual Studio Code. You can read about setting up your workspace in Opening source files in Visual Studio Code.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Automatically pretty print in the Microsoft Edge Sources Panel

In v106, this checkbox has been moved to the top and renamed to Automatically pretty print in the Sources Panel.

Ignore List for JavaScript frames on Timeline

Whether to include the Ignore list for JavaScript frames on the Timeline.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Input events on Timeline overview

Controls whether to include Input events on the Timeline overview.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Live heap profile

Controls whether to live-update the heap profile.

See also:

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Sampling heap profiler timeline

Controls whether to show the Sampling heap profiler timeline.

See also:

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Enable keyboard shortcut editor

Whether to enable editing keyboard shortcuts.

See also:

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Timeline: invalidation tracking

Controls whether to show invalidation tracking on the Timeline.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Timeline: show all events

Controls whether to show all events on the Timeline.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Timeline: V8 Runtime Call Stats on Timeline

Controls whether to show v8 runtime call stats on the Timeline.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Timeline: Replay input events

Controls whether to replay input events on the Timeline.

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Enable instrumentation breakpoints

Whether to halt at test breakpoints. This experiment makes breakpoints more reliable.

See also:

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is present in Microsoft Edge Stable v104.

Enable re-designed Breakpoint Sidebar Pane in the Sources Panel

new as of v106

Whether to show the re-designed version of the Breakpoint Sidebar pane in the Sources tool.

See also:

Status:

  • This checkbox is present in Microsoft Edge Canary v106.
  • This checkbox is not present in Microsoft Edge Stable v104.