Extension Development Host window in vscode is not showing my extension in activity bar

Question

The problem I am facing is that my Visual Studio Code extension is not appearing in the Activity Bar of the Extension Development Host window. Despite correctly defining a view container and views in the package.json file, the extension fails to show up in the Activity Bar, hindering users from accessing its functionality easily.

This is the package.json file that I am using for my extension.

"contributes": {
    "viewsContainers": {
      "activitybar": [
        {
          "id": "package-explorer",
          "title": "Package Explorer",
          "icon": "assets/icon.png"
        }
      ]
    },
    "views": {
      "package-explorer": [
        {
          "id": "package-dependencies",
          "name": "Dependencies"
        },
        {
          "id": "package-outline",
          "name": "Outline"
        }
      ]
    },
    "commands": [
      {
        "command": "cell-notifier.activate",
        "title": "Activate Cell Notifier"
      }
    ]
  },

When I run my extension using the debugger, a new Extension Development Host Visual Studio Code window opens, but my extension is not shown in the activity bar.

My extension has activated, and is shown in the page of the Developer: Show Running Extensions command