title: Flutter/Dart Extensions and intellisense not working on VSCode
body: <p>I was working with VSCode with the dart extension for months.I was facing an error on VS Code intellisense that was only showing up in my version of the repository and not on any other developers.This apparent error was not actually preventing me from running flutter run or build aar. So I assumed it was an issue with the extension itself . It was a multiple reference error for the String class between dart:convert and dart:core. I was unable to resolve the error, so I decided to uninstall and reinstall VS using the following steps : <a href="https://stackoverflow.com/questions/42603103/how-to-completely-uninstall-vscode-on-mac">How to completely uninstall vscode on mac</a></p>
  <p>Since reinstalling I have not been able get intellisense and code auto complete working.The code highlighting is working but the find references and jump to reference are not working at all.</p>
  <pre><code>Flutter doctor op:
  [✓] Flutter (Channel stable, 1.22.2, on Mac OS X 10.15.7 19H2, locale en-IN)
   
  [✓] Android toolchain - develop for Android devices (Android SDK version 29.0.3)
  [✓] Xcode - develop for iOS and macOS (Xcode 12.2)
  [!] Android Studio (version 4.1)
      ✗ Flutter plugin not installed; this adds Flutter specific functionality.
      ✗ Dart plugin not installed; this adds Dart specific functionality.
  [✓] VS Code (version 1.55.0)
  [✓] Connected device (1 available)
  
  ! Doctor found issues in 1 category.
  </code></pre>
  <p>Setting.json</p>
  <pre><code>{
      &quot;[dart]&quot;: {
          &quot;editor.formatOnSave&quot;: true,
          &quot;editor.formatOnType&quot;: true,
          &quot;editor.rulers&quot;: [
              80
          ],
          &quot;editor.selectionHighlight&quot;: false,
          &quot;editor.suggest.snippetsPreventQuickSuggestions&quot;: false,
          &quot;editor.suggestSelection&quot;: &quot;first&quot;,
          &quot;editor.tabCompletion&quot;: &quot;onlySnippets&quot;,
          &quot;editor.wordBasedSuggestions&quot;: false
      },
      &quot;files.autoSave&quot;: &quot;afterDelay&quot;,
      &quot;dart.debugExternalLibraries&quot;: false,
      &quot;dart.debugSdkLibraries&quot;: false,
      &quot;editor.multiCursorModifier&quot;: &quot;ctrlCmd&quot;,
      &quot;dart.lineLength&quot;: 1000
  }
  </code></pre>
  <p>Kindly help with the issue and let me know if other items are needed.</p>