vite.config.after.ts

import { defineConfig } from 'vite';
import react from '@vitejs/plugin-react';
import tsconfigPaths from 'vite-tsconfig-paths';
import inject from '@rollup/plugin-inject'

// https://vitejs.dev/config/
export default defineConfig({ 
  define:{
    "global":{}
  },
  plugins: [react(), tsconfigPaths()],
  build:{
    rollupOptions: {
        plugins: [inject({ Buffer: ['Buffer', 'Buffer'], process: 'process' })],
    }
  }
});

This really helped! I had to use a lowercase and uppercase buffer like: "plugins: [inject({ Buffer: ['buffer', 'Buffer'] })]" (source: vitejs/vite#6180 ) to get build working on Ubuntu.