Experimental features
Microsoft Edge DevTools provide access to experimental features that are still in development. This article lists and describes the experimental features which are in either:
- The latest version of the Canary preview channel of Microsoft Edge.
- The latest version of the Stable version 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 Stable v103:
- Enable Reporting API panel in the Application panel
- Display more precise changes in the Changes tab
- Use Lighthouse panel with timespan and snapshot modes
- Tooling for CSS layers in the Styles pane
- Enable color picking outside the browser window
- Enable webhint
- Show issues in Elements
- Focus Mode
- Open source files in Visual Studio Code
Turned on by default in Microsoft Edge Canary v105:
- Enable Reporting API panel in the Application panel
- Display more precise changes in the Changes tab
- Use Lighthouse panel with timespan and snapshot modes
- Tooling for CSS layers in the Styles pane
- Enable color picking outside the browser window
- Enable webhint
- Show issues in Elements
- Open source files in Visual Studio Code
- Enable keyboard shortcut editor
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:
To open DevTools, right-click the webpage, and then select Inspect. Or, press
Ctrl+Shift+I(Windows, Linux) orCommand+Option+I(macOS). DevTools opens.In DevTools, on the main toolbar, click the Settings (
) button. Or, press Shift+?.On the left side of the Settings panel, select the Experiments page.

On the Experiments page, select or clear the checkbox for an experiment. Some experiments are turned on (selected) by default.
Click Close (
) in the upper right to close DevTools Settings.Click the Reload DevTools button.
Restoring defaults for which experiments are selected
To restore the default settings for which experimental features are turned on:
To open DevTools, right-click the webpage, and then select Inspect. Or, press
Ctrl+Shift+I(Windows, Linux) orCommand+Option+I(macOS). DevTools opens.In DevTools, on the main toolbar, click the Settings (
) button. Or, press Shift+?. The Settings panel opens, with the Preferences page selected.At the bottom of the Preferences page, click the Restore defaults and refresh button, and then click Close (
).
Filtering the experiments
You can filter the experimental features by text included in the title.
To open DevTools, right-click the webpage, and then select Inspect. Or, press
Ctrl+Shift+I(Windows, Linux) orCommand+Option+I(macOS). DevTools opens.In DevTools, on the main toolbar, click the Settings (
) button. Or, press Shift+?. The Settings panel opens, with the Preferences page selected.On the left side of the Settings panel, select the Experiments page.
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.
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 (
) > Feedback.
List of experiments
Most of the experiments that appear in the latest version of the Canary preview channel of Microsoft Edge are listed below.
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 Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
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 Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
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:
To open DevTools, right-click the webpage, and then select Inspect. Or, press
Ctrl+Shift+I(Windows, Linux) orCommand+Option+I(macOS). DevTools opens.In DevTools, on the main toolbar, click the Settings (
) button. Or, press Shift+?. The Settings panel opens, with the Preferences page selected.On the left side of the Settings panel, select the Experiments page.
Select the Protocol Monitor checkbox, and then click Close (
) to close Settings.Open the Command Menu (
Ctrl+Shift+P), and then type protocol in the text box.Select Show Protocol monitor. The message appears: "One or more settings have changed which requires a reload to take effect."
Click the Reload DevTools button that appears next to the message.
The Protocol monitor tool is displayed in the Drawer at the bottom of DevTools.
Status:
- This checkbox is present in Microsoft Edge Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
Show CSP Violations view
Adds the CSP Violations tool, which displays any Content Security Policy (CSP) violations that are detected on the inspected webpage.

Status:
- This checkbox is present in Microsoft Edge Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
Record coverage while performance tracing
Records coverage while performance tracing.
Status:
- This checkbox is present in Microsoft Edge Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
Show option to take heap snapshot where globals are not treated as root
Shows the option to take a heap snapshot where globals are not treated as root.
See also:
Status:
- This checkbox is present in Microsoft Edge Stable v103.
- This checkbox is not present in Microsoft Edge Canary v105.
Show option to expose internals in heap snapshots
Whether to display a checkbox to expose internals in heap snapshots in the Memory tool.
See also:
Status:
- This checkbox is not present in Microsoft Edge Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
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 not present in Microsoft Edge Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
Timeline: event initiators
Whether to include event initiators in the Timeline.
Status:
- This checkbox is present in Microsoft Edge Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
Timeline: WebGL-based flamechart
Whether to use a WebGL-based flamechart in the Timeline.
Status:
- This checkbox is present in Microsoft Edge Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
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 Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
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 Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
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:
- New color contrast calculation - Advanced Perceptual Contrast Algorithm (APCA) in What's New in DevTools (Microsoft Edge 89).
- Change colors with the Color Picker in CSS features reference.
- Test text-color contrast using the Color Picker
Status:
- This checkbox is present in Microsoft Edge Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
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 Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
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:
To open DevTools, right-click the webpage, and then select Inspect. Or, press
Ctrl+Shift+I(Windows, Linux) orCommand+Option+I(macOS). DevTools opens.In DevTools, on the main toolbar, select the Elements tab. If the Elements tab isn't visible, click the More tabs (
) button, or else the More Tools (
) button.In the Styles tab, select the Font Editor icon.

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 Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
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 Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
Enable experimental cookie features
Enables experimental cookie features.
Status:
- This checkbox is present in Microsoft Edge Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
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 Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
Display more precise changes in the Changes tab
See More precise changes in the Changes tab.
Status:
- This checkbox is present in Microsoft Edge Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
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 Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
Local overrides for response headers
Whether to use local overrides for response headers.
Status:
- This checkbox is present in Microsoft Edge Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
Enable CSS Authoring hints for inactive rules, deprecated properties, etc.
Whether to enable CSS authoring hints in the Styles panel of the Elements tool to display information tooltips next to inactive or deprecated properties.
In Canary v105, this checkbox has no effect. When this feature is implemented, this feature will provide help when writing or inspecting CSS in the Styles panel. Small information icons will appear next to CSS properties that are inactive (or deprecated).
Status:
- This checkbox is not present in Microsoft Edge Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
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 Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
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 Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
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 (
) button. The mouse cursor becomes an eyedropper. Click anywhere on your monitor to select a color.
See also:
- Change colors with the Color Picker in CSS features reference
Status:
- This checkbox is present in Microsoft Edge Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
Group sources into Authored and Deployed trees
Controls whether to group sources into Authored and Deployed trees in the Page, Filesystem, and Overrides tabs 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 not present in Microsoft Edge Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
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 Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
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.

Status:
- This checkbox is present in Microsoft Edge Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
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 Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
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 Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
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.

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 Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
Automatically pretty print in the Microsoft Edge 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:
- This checkbox is present in Microsoft Edge Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
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 Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
Input events on Timeline overview
Controls whether to include Input events on the Timeline overview.
Status:
- This checkbox is present in Microsoft Edge Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
Live heap profile
Controls whether to live-update the heap profile.
See also:
Status:
- This checkbox is present in Microsoft Edge Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
Sampling heap profiler timeline
Controls whether to show the Sampling heap profiler timeline.
See also:
Status:
- This checkbox is present in Microsoft Edge Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
Enable keyboard shortcut editor
Whether to enable editing keyboard shortcuts.
See also:
Status:
- This checkbox is not present in Microsoft Edge Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
Timeline: invalidation tracking
Controls whether to show invalidation tracking on the Timeline.
Status:
- This checkbox is present in Microsoft Edge Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
Timeline: show all events
Controls whether to show all events on the Timeline.
Status:
- This checkbox is present in Microsoft Edge Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
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 Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
Timeline: Replay input events
Controls whether to replay input events on the Timeline.
Status:
- This checkbox is present in Microsoft Edge Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
Enable instrumentation breakpoints
Whether to halt at test breakpoints. This experiment makes breakpoints more reliable.
See also:
- Enable synchronization on instrumentation breakpoints
- The first time source files are loaded, breakpoints might not trigger
Status:
- This checkbox is not present in Microsoft Edge Stable v103.
- This checkbox is present in Microsoft Edge Canary v105.
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