No Hassle Visual Code Theming: Publishing an Extension

No Hassle Visual Code Theming: Publishing an Extension

Publishing a VS Code extension is a crucial step in sharing your theme with others, but it can be a complex process, with a notable example being the trouble encountered by the author in setting up an Azure DevOps account, which took several days to resolve. The process involves publishing your theme to multiple platforms, including Visual Studio Marketplace and Open VSX, with a significant fact being that VS Code uses the Visual Studio Marketplace, while other text editors like Cursor use Open VSX.

Why This Matters

The technical reality of publishing a VS Code extension is far from the ideal model of a straightforward, one-click process, with the author encountering several problems, including a hanging backend and difficulty finding the right page, resulting in a significant amount of time wasted, with an estimated cost of several days of productivity. The failure to publish an extension can result in a significant loss of potential users, with a notable example being the author’s theme, Twilight Cosmos, which could have been enjoyed by many users if the publishing process was smoother.

Key Insights

• The Visual Studio Marketplace requires a personal access token from an Azure DevOps account to publish an extension, with a maximum expiry of one year, as of 2026.
• Open VSX uses a lifetime access token, eliminating the need for frequent token updates, as of 2026.
• The vsce command-line tool is used to publish extensions to the Visual Studio Marketplace, with a success rate of 100% after initial setup, as reported by the author.

Working Example

{
  "name": "twilight-cosmos-theme",
  "icon": "path/to/icon.png",
  "contributes": {
    "themes": [
      {
        "label": "Twilight Cosmos",
        "uiTheme": "vs-dark",
        "path": "./path-to-theme.json"
      }
    ]
  },
  "keywords": [
    "theme",
    "dark theme",
    "twilight",
    "cosmos",
    "color-theme",
    "dark",
    "purple",
    "blue",
    "vscode-theme"
  ]
}

Practical Applications

• Use Case: The author’s theme, Twilight Cosmos, is a prime example of a VS Code extension that can be published to multiple platforms, including Visual Studio Marketplace and Open VSX, with a significant benefit being the ability to share the theme with a wide range of users.
• Pitfall: Failing to include a contributes key in the package.json file can prevent the theme from being discovered by VS Code and other text editors, resulting in a significant loss of potential users.

References:

• https://css-tricks.com/no-hassle-visual-code-theming-publishing-an-extension/
• https://docs.microsoft.com/en-us/azure/devops/marketplace/creating-and-publishing
• https://open-vsx.org/