[Feature Request] Improve Compatibility of Utility Classes with UnoCSS/Tailwind

[trydofor]

Background

Currently, I'm exploring ways to disable the built-in utility classes in favor of using unocss (or TailwindCSS via unocss presets) in my project. I’ve found some related behavior:

• Fully disabling utility classes causes issues #18846
• Icons already support unocss via a preset, which is great!

Goal

In my project, I aim to:

• ✅ Use unocss instead of built-in utility classes wherever possible
• ❌ Disable Vuetify utility classes selectively — only when safe
• 🧱 For unsafe cases, block them via unocss’s blocklist

Problem

Currently, I’m unclear on the compatibility boundaries between Vuetify utility classes and unocss. Specifically:

• Which Vuetify utility classes are safe to disable?
• Which utility classes should be explicitly blocked in unocss to avoid conflicts?

Proposed Idea

Would it be possible to:

• Provide a Vuetify-compatible UnoCSS preset or config helper
• Or publish an official list of utility classes that:
  • ✅ Can be safely replaced by unocss
  • 🧱 Should be included in a blocklist

This would greatly help in customizing and reducing conflicts when using unocss in Vuetify-based projects.

---

Question

Has anyone already explored this direction?
Any recommended strategy or best practice for gradually migrating to unocss with minimal friction?

Thanks in advance!

[AndreyYolkin]

Currently, the most safe option currently is to use prefixed uno (u-flex, u-mt-2). It prevents name collisions. As for Vuetify utilities: you 100% need to keep everything related to flex to make VRow/VCol works (PR aimed to resolve this is cooking), and not sure about other things, might rounded/elevation utilities also be need to stay. Things are likely to be changed, so stay tuned

[trydofor]

Currently, the most safe option currently is to use prefixed (u-flex, u-mt-2).

Thanks @AndreyYolkin for the reply — I’ll keep following the updates!

The u-* utility classes do tend to get a bit verbose 😅.
For now, I’m planning to block all utility classes in uno blocklist as a temporary workaround.

It would be great if Vuetify offered an option to prefix utility classes with v- instead — that would make things feel more consistent and customizable.

---

scripts to extract blocked class name,
✅ exectract 3405 vuetify class to ./configures/vuetify-utility-classes.mjs

import fs from 'fs/promises';
import path from 'path';
import { fileURLToPath } from 'url';

const cssPaths = [
  path.resolve('node_modules/vuetify/dist/vuetify.css'),
  path.resolve('node_modules/vuetify/dist/vuetify-labs.css'),
];

const classPrefix = [
  'border', // https://vuetifyjs.com/en/styles/borders/#usage
  'rounded', // https://vuetifyjs.com/en/styles/border-radius/#usage
  'cursor', // https://vuetifyjs.com/en/styles/cursor/#usage
  'd-', // https://vuetifyjs.com/en/styles/display/#usage
  'elevation', // https://vuetifyjs.com/en/styles/elevation/#usage
  'flex-', 'ga-', 'justify-', 'align-', 'order-', // https://vuetifyjs.com/en/styles/flex/#usage
  'float-', // https://vuetifyjs.com/en/styles/float/#usage
  'opacity-', // https://vuetifyjs.com/en/styles/opacity/#usage
  'overflow', // https://vuetifyjs.com/en/styles/overflow/#usage
  'position-', 'top-', 'right-', 'bottom-', 'left-', // https://vuetifyjs.com/en/styles/position/#usage
  'h-', 'fill-', 'height-', 'w-', // https://vuetifyjs.com/en/styles/sizing/#usage
  'ga-', 'ma-', 'ml-', 'ms-', 'mt-', 'mr-', 'me-', 'mb-', // https://vuetifyjs.com/en/styles/spacing/#usage
  'ga-', 'pa-', 'pl-', 'ps-', 'pt-', 'pr-', 'pe-', 'pb-', // https://vuetifyjs.com/en/styles/spacing/#usage
  'text-', // https://vuetifyjs.com/en/styles/text-and-typography/#usage
];

const classRegex = /\.([a-zA-Z0-9\-_\\:]+)[\s,{]/g;
const classSet = new Set<string>();

for (const cssPath of cssPaths) {
  const css = await fs.readFile(cssPath, 'utf-8');

  let match;
  while ((match = classRegex.exec(css)) !== null) {
    const className = match[1].replace(/\\:/g, ':');
    if (classPrefix.some(it => className.startsWith(it))) {
      classSet.add(className);
    }
  }
}

const classArr = [...classSet];
classArr.sort();
const blockOut = fileURLToPath(import.meta.url).replace(/\.[^.]+$/, '.mjs');
const blockArr = 'export default ' + JSON.stringify(classArr, null, 2).replaceAll('"', '\'');
await fs.writeFile(blockOut, blockArr);
console.log(`✅ exectract ${classSet.size} vuetify class to ${blockOut}`);

---

// uno.config.ts
import { mergeConfigs } from '@unocss/core';
import blocklist from './configures/vuetify-utility-classes.mjs';

export default mergeConfigs({
  /*
   * https://vuetifyjs.com/en/features/sass-variables/#disabling-utility-classes
   * https://github.com/vuetifyjs/vuetify/blob/master/packages/vuetify/src/styles/settings/_variables.scss
   */
  blocklist,
}]);

[userquin]

I will try to include this in the new version, utilities at vuetify sass/scss is a pain

[trydofor]

presetUno({ prefix: ['_', ''] }) with blocklist works