ui Internal server error: [postcss] postcss-import: Unknown word

Environment

Operating System: Linux
Bun Version: v1.1.29
Vue Version: v3.5.13
Vite Version: v5.4.11
Package Manager: [email protected]

Is this bug related to Nuxt or Vue?

Vue

Version

v3.0.0-alpha.9

Reproduction

Unable to run on https://stackblitz.com/edit/vitejs-vite-2s99rp because of https://github.com/stackblitz/core/issues/1855 (I think) but I'll create a repo as soon as I can.

Description

After following the setup tutorial for the installation of Nuxt UI in a Vue-only environment and running the project, I get an error (see logs). The only different thing in the setup I had to do is that, as I am building a custom element, I did:

const Widget = defineCustomElement(App, {
	configureApp(app) {
		app.use(ui)
		app.use(i18n)
		app.provide(I18nInjectionKey, i18n)
	},
})

Instead of the usual createApp method. Did I miss something?

Additional context

No response

Logs

15:53:45 [vite] Internal server error: [postcss] postcss-import: /home/dany/Documenti/GitHub/chat-widget/node_modules/@nuxt/ui/dist/module.mjs:1:16: Unknown word
  Plugin: vite:css
  File: /home/dany/Documenti/GitHub/chat-widget/node_modules/@nuxt/ui/dist/module.mjs:1:15
  1  |  import defu, { defu as defu$1 } from 'defu';
     |                 ^
  2  |  import { defineNuxtModule, createResolver, addVitePlugin, addPlugin, addComponentsDir, addImportsDir, extendPages, hasNuxtModule, installModule } from '@nuxt/kit';
  3  |  import { d as defaultOptions, r as resolveColors, a as getDefaultUiConfig, b as addTemplates, c as buildTemplates } from './shared/ui.d52SSCwA.mjs';
      at Input.error (/home/dany/Documenti/GitHub/chat-widget/node_modules/postcss/lib/input.js:106:16)
      at Parser.unknownWord (/home/dany/Documenti/GitHub/chat-widget/node_modules/postcss/lib/parser.js:593:22)
      at Parser.other (/home/dany/Documenti/GitHub/chat-widget/node_modules/postcss/lib/parser.js:435:12)
      at Parser.parse (/home/dany/Documenti/GitHub/chat-widget/node_modules/postcss/lib/parser.js:470:16)
      at parse (/home/dany/Documenti/GitHub/chat-widget/node_modules/postcss/lib/parse.js:11:12)
      at get root [as root] (/home/dany/Documenti/GitHub/chat-widget/node_modules/postcss/lib/no-work-result.js:119:14)
      at Result.get [as root] (/home/dany/Documenti/GitHub/chat-widget/node_modules/postcss/lib/no-work-result.js:27:21)
      at loadImportContent (file:///home/dany/Documenti/GitHub/chat-widget/node_modules/vite/dist/node/chunks/dep-C6EFp3uH.js:867:33)
      at async Promise.all (index 0)
      at async resolveImportId (file:///home/dany/Documenti/GitHub/chat-widget/node_modules/vite/dist/node/chunks/dep-C6EFp3uH.js:800:27)
15:53:45 [vite] Pre-transform error: [postcss] postcss-import: /home/dany/Documenti/GitHub/chat-widget/node_modules/@nuxt/ui/dist/module.mjs:1:16: Unknown word

Dec 03 '24 16:12 zAlweNy26

I have the exact same issue when trying to use Tailwinds's @source "PATH"

Dec 07 '24 12:12 izoukhai

if you find any solutions, please let me know

Dec 13 '24 19:12 karombekHusanov

I don't understand why postcss-import is trying to process a js file. I thought it was something with my setup, but everything seems fine. I'm still unable to find a solution for this.

Dec 19 '24 10:12 zAlweNy26

Kept getting similar errors with "@nuxt/ui": "^2.21.1", on clean setup

 ERROR  Pre-transform error: [postcss] postcss-import: /home/.../nuxt-app/node_modules/tailwindcss/lib/index.js:1:1: Unknown word "use strict"               07:55:00
  Plugin: vite:css
  File: /home/.../nuxt-app/node_modules/tailwindcss/lib/index.js:1:0
  1  |  "use strict";
     |  ^
  2  |  module.exports = require("./plugin");
  3  |

upgrading @nuxt/ui to ^3.0.0 by modifying package.json and rm -rf node_modules .nuxt package-lock.json; npm install solved those errors

Mar 15 '25 05:03 tumoxep

Are you sure you're adding TailwindCSS v4 correctly? A lot has changed since v3.

Unknown word "use strict" error by upgrading TailwindCSS from v3 to v4

Apr 02 '25 07:04 rozsazoltan

Would you be able to provide a reproduction? 🙏

More info

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May 15 '25 14:05 github-actions[bot]

The issue seems to be fixed after the package went out of the beta

May 15 '25 15:05 zAlweNy26