# DevTools 2.8.0 release notes

> Release notes for Dart and Flutter DevTools version 2.8.0.



The 2.8.0 release of the Dart and Flutter DevTools
includes the following changes among other general improvements.
To learn more about DevTools, check out the
[DevTools overview](https://docs.flutter.dev/tools/devtools).

## General updates

* Improvements for initial page load time -
  [#3325](https://github.com/flutter/devtools/pull/3325)
* Performance improvements for connecting DevTools to a device,
  particularly impactful for low-memory devices -
  [#3468](https://github.com/flutter/devtools/pull/3468)
* For users on Flutter 2.8.0 or greater (or Dart 2.15.0 or greater),
  DevTools should now be launched via the `dart devtools` command
  instead of running `pub global activate devtools`.
  DevTools 2.8.0 will be the last version of DevTools shipped on pub,
  and all future versions of DevTools will be shipped as part of the Dart SDK.
  If you see this warning,
  be sure to open DevTools via `dart devtools` instead of from pub:

  ![dart devtools warning dialog](/assets/images/docs/tools/devtools/release-notes/images-2.8.0/image1.png "dart devtools warning dialog")

## Performance updates

* Added a new "Enhance Tracing" feature to help users diagnose UI jank
  stemming from expensive Build, Layout, and Paint operations.

  ![Enhance tracing](/assets/images/docs/tools/devtools/release-notes/images-2.8.0/image2.png "Enhance tracing")

  The expected workflow is as such:

  1. User is investigating UI jank in the performance page
  2. User notices a long Build, Layout, and/or Paint event
  3. User turns on the respective tracking toggle in the "Enhance Tracing" feature
  4. User reproduces the UI jank in their app
  5. User looks at the new set of Timeline events, which should now have
     additional child events for widgets built, render objects laid out,
     and/or render objects painted

  ![Timeline events](/assets/images/docs/tools/devtools/release-notes/images-2.8.0/image3.png "Timeline events")

* Added new "More debugging options" feature to allow for disabling
  rendering layers for Clip, Opacity, and Physical Shapes.

  ![More debugging options](/assets/images/docs/tools/devtools/release-notes/images-2.8.0/image4.png "More debugging options")

  The expected workflow is as such:

  1. User is investigating UI jank in the performance page
  2. User notices a lot of janky frames and suspects it could be due to
     excessive use of clipping, opacity, or physical shapes.
  3. User turns off the respective render layer toggle in the "More
     debugging options" feature
  4. User reproduces the UI jank in their app
  5. If the UI jank is reduced with a rendering layer turned off,
     the user should try to optimize their app to use
     less clipping/opacity/physical shape effects.
     If the UI jank is not reduced,
     the user now knows that the performance problem
     is not due to these UI effects.

## Debugger updates

* Replaced the "Libraries" pane with a "File Explorer" pane -
  [#3448](https://github.com/flutter/devtools/pull/3448).
  The "File Explorer" pane has two components:

  1. A tree view of the libraries present in your application.
     You can use the File Explorer to find and open a library,
     or you can use the existing <kbd>Ctrl</kbd> / <kbd>Cmd</kbd> +
     <kbd>P</kbd> keyboard shortcut to search for a file.
  1. A new "Outline" view that shows the structure of the selected library.
     This view will show classes, members, methods, etc.,
     and when an item is selected,
     the source view will jump to the respective line of code
     for the selected item.

  ![Outline view selected library](/assets/images/docs/tools/devtools/release-notes/images-2.8.0/image5.png "Outline view selected library")

* Performance improvements to expression evaluation auto complete -
  [#3463](https://github.com/flutter/devtools/pull/3463)
* Fixed a bug with keyboard shortcuts -
  [#3458](https://github.com/flutter/devtools/pull/3458)
* UI polish - [#3421](https://github.com/flutter/devtools/pull/3421),
  [#3449](https://github.com/flutter/devtools/pull/3449)

## Full commit history

To find a complete list of changes since the previous release,
check out
[the diff on GitHub](https://github.com/flutter/devtools/compare/v2.7.0...v2.8.0).