Steps to reproduce:

• Clone repo.
• Open webview-codicons-sample folder with VS Code.
• Run npm i.
• Install packaging cli via npm i -g vsce.
• Remove publisher line from package.json (otherwise you'll get the error message It's not allowed to use the 'vscode-samples' publisher.).
• Run vsce package.
• Go to the extensions tab and install the freshly created .vsix file.
• Run the command Cat Codicons: Show Cat Codicons.

The result (at least for me), was a tab looking like this:

I opened the .vsix file manually and looked inside - and the codicons are nowhere to be found inside. Which begs the question: What am I missing when it comes to packaging? How would I best go about it with a project created with the yeoman generator as described in the official tutorials? Just add !node_modules/@vscode/codicons/dist/** to the .vscodeignore file?