Embedded DevTools window is empty with "Not found" message

[Ruzo]

When Dev Tools Location is set to beside or active, the embedded DevTools window is empty with only a "Not found" message.

Steps to reproduce the behavior:

1. In settings, choose beside or active as the Dev Tools Location option.
2. Start debugging

Expected behavior An embedded DevTools window containing widget trees information.

Screenshots

Please complete the following information:

• Operating System and version: macOs Monterey - version 12.4
• VS Code version: 1.68.0-insider
• Dart extension version: v3.42.1
• Dart/Flutter SDK version: Channel beta, 3.1.0
• Target device (if the issue relates to Flutter debugging): Any

[Ruzo]

This issue was created as per @DanTup's request.

The workaround Dan provided was to add a custom Dev Tools Port that is not in the range 9100-9110 (for example, 9199)

[DanTup]

I suspect once https://github.com/flutter/devtools/issues/3896 is solved this problem may go away, but I'll keep this open for now to collect info in case there's some additional going on when embedded in VS Code.

[DanTup]

In https://github.com/flutter/devtools/issues/4417, @Noahbanderson reported that after upgrading the Flutter 3.3 the issue didn't come back even after removing the port number. I wonder whether something that changed that bypassed the old cache. I'd be interested to know if the same is true for you.

[Ruzo]

Hi @DanTup, I've been using 3.3 since beta and I'm on Flutter 3.3.0-0.5.pre • channel beta right now. I've just tried removing the port number and it seems to be working perfectly without it.

[DanTup]

Great! I suspect some of the caching changes made in DevTools have probably resolved this particular issue then. I'll close this, but if you (or anyone else) sees this again on >= Flutter 3.3 / Dart 2.18, please let me know.