Skip to content

Update "Experimental features in Edge DevTools" - #3875

Open
mikehoffms wants to merge 3 commits into
mainfrom
user/mikehoffms/devtools-experiments-150
Open

Update "Experimental features in Edge DevTools"#3875
mikehoffms wants to merge 3 commits into
mainfrom
user/mikehoffms/devtools-experiments-150

Conversation

@mikehoffms

@mikehoffms mikehoffms commented Jul 23, 2026

Copy link
Copy Markdown
Collaborator

Rendered article sections for review:

AB#63239044

@mikehoffms mikehoffms added cat: devtools DevTools-related content. in-progress labels Jul 23, 2026
@mikehoffms
mikehoffms marked this pull request as draft July 23, 2026 17:33
@learn-build-service-prod

Copy link
Copy Markdown
Contributor

Learn Build status updates of commit 107e6ca:

✅ Validation status: passed

File Status Preview URL Details
microsoft-edge/devtools/experimental-features/index.md ✅Succeeded View

For more details, please refer to the build report.

@mikehoffms
mikehoffms marked this pull request as ready for review July 23, 2026 20:12
@learn-build-service-prod

Copy link
Copy Markdown
Contributor

Learn Build status updates of commit 5a012cb:

⚠️ Validation status: warnings

File Status Preview URL Details
microsoft-edge/devtools/inspect-styles/edit-fonts.md ⚠️Warning View Details
microsoft-edge/devtools/whats-new/2021/01/devtools.md ⚠️Warning View Details
microsoft-edge/devtools/whats-new/2024/08/devtools-128.md ⚠️Warning View Details
microsoft-edge/devtools/experimental-features/index.md ✅Succeeded View

microsoft-edge/devtools/inspect-styles/edit-fonts.md

  • Line 26, Column 15: [Warning: bookmark-not-found - See documentation] Cannot find bookmark '#enable-new-font-editor-within-the-styles-tab' in 'devtools/experimental-features/index.md'.

microsoft-edge/devtools/whats-new/2021/01/devtools.md

  • Line 71, Column 3: [Warning: bookmark-not-found - See documentation] Cannot find bookmark '#enable-new-font-editor-within-the-styles-tab' in 'devtools/experimental-features/index.md'.
  • Line 511, Column 3: [Warning: bookmark-not-found - See documentation] Cannot find bookmark '#enable-new-advanced-perceptual-contrast-algorithm-apca-replacing-previous-contrast-ratio-and-aaaaa-guidelines' in 'devtools/experimental-features/index.md'.

microsoft-edge/devtools/whats-new/2024/08/devtools-128.md

  • Line 63, Column 113: [Warning: bookmark-not-found - See documentation] Cannot find bookmark '#show-option-to-expose-internals-in-heap-snapshots' in 'devtools/experimental-features/index.md'.

For more details, please refer to the build report.

Note: Your PR may contain errors or warnings or suggestions unrelated to the files you changed. This happens when external dependencies like GitHub alias, Microsoft alias, cross repo links are updated. Please use these instructions to resolve them.


Whether to display a checkbox to expose internals in heap snapshots in the **Memory** tool.
<!-- todo old: need text -->
todo: need desc

@mikehoffms mikehoffms Jul 23, 2026

Copy link
Copy Markdown
Collaborator Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

@learn-build-service-prod

Copy link
Copy Markdown
Contributor

PoliCheck Scan Report

The following report lists PoliCheck issues in PR files. Before you merge the PR, you must fix all severity-1 and severity-2 issues. The AI Review Details column lists suggestions for either removing or replacing the terms. If you find a false positive result, mention it in a PR comment and include this text: #policheck-false-positive. This feedback helps reduce false positives in future scans.

✅ No issues found

More information about PoliCheck

Information: PoliCheck | Severity Guidance | Term
For any questions: Try searching the learn.microsoft.com contributor guides or post your question in the Learn support channel.


See also:
* [Record heap snapshots using the Memory tool ("Heap snapshot" profiling type)](../memory-problems/heap-snapshots.md)
* [] todo

@mikehoffms mikehoffms Jul 23, 2026

Copy link
Copy Markdown
Collaborator Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

* 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.
todo: need desc

@mikehoffms mikehoffms Jul 23, 2026

Copy link
Copy Markdown
Collaborator Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

* [New color contrast calculation - Advanced Perceptual Contrast Algorithm (APCA)](../whats-new/2021/01/devtools.md#new-color-contrast-calculation---advanced-perceptual-contrast-algorithm-apca) in _What's new in DevTools (Microsoft Edge 89)_.
* [Change colors with the Color Picker](../css/reference.md#change-colors-with-the-color-picker) in _CSS features reference_.
* [Test text-color contrast using the Color Picker](../accessibility/color-picker.md)
* [] todo

@mikehoffms mikehoffms Jul 23, 2026

Copy link
Copy Markdown
Collaborator Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

## JPEG XL support

This experiment improves the **Performance** tool's **Main** section to help you quickly identify `postMessage` events and handlers, by distinguishing events that are triggered by the `postMessage` method from other events that are displayed in the **Performance** tool. This experiment helps you investigate performance issues that are related to posting messages across various threads of an application, to view messages between windows, iframes, and dedicated workers.
todo: desc

@mikehoffms mikehoffms Jul 23, 2026

Copy link
Copy Markdown
Collaborator Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

* [postMessage Trace Events demo (rendered)](https://microsoftedge.github.io/Demos/devtools-postmessage-perf-timeline/)
* [postMessage Trace Events demo (source code)](https://github.com/MicrosoftEdge/Demos/tree/main/devtools-postmessage-perf-timeline)
* [postMessage events and handlers are distinguished from other events](../whats-new/2024/04/devtools-124.md#postmessage-events-and-handlers-are-distinguished-from-other-events) in _What's new in DevTools (Microsoft Edge 124)_.
todo: see also

@mikehoffms mikehoffms Jul 23, 2026

Copy link
Copy Markdown
Collaborator Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

## Show "+" button on the tab strip for adding tools

Controls whether to show all events in the **Performance** tool.
todo: desc

@mikehoffms mikehoffms Jul 23, 2026

Copy link
Copy Markdown
Collaborator Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

_new as of Microsoft Edge 128_

Adds a **Trace Event** section to the **Summary** tab of the **Performance** tool. The **Trace Event** section is displayed when you select an event in a recorded performance trace. The **Trace Event** section displays debugging information about the selected trace event, such as its name and duration.
* [] todo

@mikehoffms mikehoffms Jul 23, 2026

Copy link
Copy Markdown
Collaborator Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Labels

cat: devtools DevTools-related content.

Projects

None yet

Development

Successfully merging this pull request may close these issues.

1 participant