Bug Description

When running with terser-webpack-plugin 5.3.15, a generated file that should be empty is no longer empty.

Link to Minimal Reproduction and step to reproduce

1. In an empty directory, run npm add webpack webpack-cli terser-webpack-plugin
2. Create the following webpack.config.js:

   module.exports = {
       mode: 'production',
       entry: './src/index.js',
   };

3. Create the following file at src/index.js:

   // This module is empty.

4. Run npm exec webpack
5. Examine the generated dist/main.js file.

Expected Behavior

The file dist/main.js is 0 bytes.

Actual Behavior

The file dist.main.js has the following content:

/******/ (() => { // webpackBootstrap
// This module is empty.

/******/ })()

Environment

System:
    OS: Linux 6.17 Debian GNU/Linux forky/sid
    CPU: (16) x64 AMD Ryzen 7 7840U w/ Radeon  780M Graphics
    Memory: 23.73 GB / 30.66 GB
  Binaries:
    Node: 22.21.0 - /usr/bin/node
    Yarn: 1.22.22 - /usr/local/bin/yarn
    npm: 10.9.4 - /usr/bin/npm
    pnpm: 10.25.0 - /usr/local/bin/pnpm
  Browsers:
    Firefox: 145.0.1
    Firefox Developer Edition: 145.0.1
  Packages:
    terser-webpack-plugin: ^5.3.15 => 5.3.15 
    webpack: ^5.103.0 => 5.103.0 
    webpack-cli: ^6.0.1 => 6.0.1

Is this a regression?

Yes (please specify version below)

Last Working Version

5.3.14

Additional Context

In production, what we're mostly seeing is

/******/ (() => { // webpackBootstrap
/******/        "use strict";
// extracted by mini-css-extract-plugin

/******/ })()
;

for modules where https://www.npmjs.com/package/mini-css-extract-plugin has extracted the CSS and there is no JS code in the module. With earlier versions of terser-webpack-plugin these were empty files.