Repro steps:

• Debug hello_world example for web platform using latest flutter version on master channel
• Open widget inspector
• (May need to stop and start the debugger again)
• Observe several errors in the debug console mentioning (-32601) Unknown method "_flutter.listViews".

I added some printing and found that the calls to failing extension services are coming from dart-code VSCode extension and the errors happen at

Flutter doctor -v
[✓] Flutter (Channel master, 2.3.0-1.0.pre.170, on Mac OS X 10.15.7 19H524
darwin-x64, locale en-US)
• Flutter version 2.3.0-1.0.pre.170 at /Users/annagrin/source/flutter/flutter
• Upstream repository git@github.com:annagrin/flutter.git
• Framework revision 027d4ec (5 hours ago), 2021-04-29 10:56:57 -0700
• Engine revision e7939e0
• Dart version 2.14.0 (build 2.14.0-48.0.dev)

[✓] Android toolchain - develop for Android devices (Android SDK version 29.0.3)
• Android SDK at /Users/annagrin/Library/Android/sdk
• Platform android-29, build-tools 29.0.3
• Java binary at: /Applications/Android
Studio.app/Contents/jre/jdk/Contents/Home/bin/java
• Java version OpenJDK Runtime Environment (build
1.8.0_212-release-1586-b4-5784211)
• All Android licenses accepted.

[✓] Xcode - develop for iOS and macOS
• Xcode at /Applications/Xcode.app/Contents/Developer
• Xcode 12.4, Build version 12D4e
• CocoaPods version 1.10.1

[✓] Chrome - develop for the web
• Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

[✓] Android Studio (version 3.6)
• Android Studio at /Applications/Android Studio.app/Contents
• Flutter plugin version 45.1.1
• Dart plugin version 192.7761
• Java version OpenJDK Runtime Environment (build
1.8.0_212-release-1586-b4-5784211)

[✓] IntelliJ IDEA Community Edition (version 2021.1)
• IntelliJ at /Applications/IntelliJ IDEA CE.app
• Flutter plugin version 55.1.5
• Dart plugin version 211.6693.108

[✓] VS Code (version 1.55.2)
• VS Code at /Applications/Visual Studio Code.app/Contents
• Flutter extension version 3.21.0

[✓] Connected device (2 available)
• macOS (desktop) • macos • darwin-x64 • Mac OS X 10.15.7 19H524
darwin-x64
• Chrome (web) • chrome • web-javascript • Google Chrome 90.0.4430.93

• No issues found!