Tailwind CSS Intellisense VSCode Extension Not Working with Angular 20

[warrendodsworth]

Seeing Can't Find Project in VSCode Output panel

Followed the guide to add tailwind to an Angular project.
Tailwind CSS Intellisense works in Angular 19 until a .postcssrc.json file is added to the project root.

Guide: https://tailwindcss.com/docs/installation/framework-guides/angular
Potential issue: Angular 20 requires using @use 'tailwindcss' as '*';
Output from VSCode Tailwind CSS Intellisense Extension.

Locating server…
Booting server...
Setting up server…
Listening for messages…
Searching for Tailwind CSS projects in the workspace's folders.
{"tailwind":{"version":"4.1.13","features":["css-at-theme","layer:base","content-list","source-inline","source-not"],"isDefaultVersion":false},"path":"/Users/w/Documents/github_clone/ng20-demo/src/app/core/styles/_tailwind.scss"}
[Warn  - 09:41:31] The config /Users/w/Documents/github_clone/ng20-demo/src/app/core/styles/_tailwind.scss requires a preprocessor and is not supported by Tailwind CSS v4.0.
{"tailwind":{"version":"4.1.13","features":["css-at-theme","layer:base","content-list","source-inline","source-not"],"isDefaultVersion":false},"path":"/Users/w/Documents/github_clone/ng20-demo/tailwind.config.js"}
[Global] Creating projects: []
[Global] Preparing projects...
[Global] Initializing projects...
[Info  - 09:41:31] [GLOBAL] No matching project for document {
  fsPath: '/Users/w/Documents/github_clone/ng20-demo/tailwind.config.js',
  normalPath: '/Users/w/Documents/github_clone/ng20-demo/tailwind.config.js'
}

How to resolve this?

[wongjn]

I see in the logs you helpfully provided, it mentions a _tailwind.scss file. As per the documentation:

Tailwind CSS v4.0 is a full-featured CSS build tool designed for a specific workflow, and is not designed to be used with CSS preprocessors like Sass, Less, or Stylus.

Think of Tailwind CSS itself as your preprocessor — you shouldn't use Tailwind with Sass for the same reason you wouldn't use Sass with Stylus.

Note in the documentation you linked, for step 4, it says to:

Add an @import to ./src/styles.css that imports Tailwind CSS.

Notice how it says to add it to a .css file.