Nuxt: PostCSS warning (spam) preventing proper server initialization

[UltraCakeBakery]

Nuxt basically spams my console with the following message:

 WARN  You did not set any plugins, parser, or stringifier. Right now, PostCSS does nothing. Pick plugins for your case on https://www.postcss.parts/ and use them in postcss.config.js.

My package.json:

    "dependencies": {
       "@nuxtjs/axios": "^5.12.5",
       "@nuxtjs/pwa": "^3.3.5",
       "core-js": "^3.8.3",
       "nuxt": "^2.15.0"
   },
   "devDependencies": {
       "@nuxtjs/eslint-config": "^5.0.0",
       "@nuxtjs/eslint-module": "^3.0.2",
       "@vue/test-utils": "^1.1.2",
       "babel-core": "7.0.0-bridge.0",
       "babel-eslint": "^10.1.0",
       "babel-jest": "^26.6.3",
       "eslint": "^7.18.0",
       "eslint-plugin-nuxt": "^2.0.0",
       "eslint-plugin-vue": "^7.5.0",
       "jest": "^26.6.3",
       "vue-jest": "^3.0.4",
       "vue-windicss-preprocess": "^2.0.0"
   }

My nuxt.config.js has the code from https://windicss.netlify.app/guide/vue.html#nuxt added.
My tailwind config follows all the instructions from https://windicss.netlify.app/guide/migration.html
I have no postcss.config, as this is not specified in the docs.

Is there a key configuration part I'm missing?

[reslear]

See

vue-windicss-preprocess/examples/nuxt-ca-ts/package.json

Line 15 in 3b1519f

"devDependencies": {