metamorpov/rollup.config.js

import resolve from '@rollup/plugin-node-resolve';
import commonjs from '@rollup/plugin-commonjs';
import json from '@rollup/plugin-json';

export default [
  {
    input: 'src/save-load-options.js',
    output: {
      file: 'src/popup.js',
      format: 'iife',
        name: 'popup'
    },
    plugins: [resolve(), commonjs(), json()]
  },

  {
    input: 'src/replace-words.js',
    output: {
      file: 'src/content-script.js',
      format: 'iife',
        name: 'contentScript'
    },
    plugins: [resolve(), commonjs(), json()]
  }
];