webpack-dev-server: Browser reloads infinitely when using multi-compiler mode

• This is a bug
• This is a modification request

Code

See full example repository for reproduction here

// webpack.config.js
const HtmlWebpackPlugin = require('html-webpack-plugin');
const path = require('path');

module.exports = [
    {
    mode: 'development',
    entry: './temp2.js',
    output: {
      filename: 'main2.js',
      path: path.resolve(__dirname, 'dist'),
    },
        plugins: [
            new HtmlWebpackPlugin(),
        ],
    },
    {
        mode: 'development',
        entry: './temp.js',
      output: {
        filename: 'main1.js',
        path: path.resolve(__dirname, 'dist'),
      },
    },
];

Please paste the results of npx webpack-cli info here, and mention other relevant information

  System:
    OS: macOS 11.5.2
    CPU: (12) x64 Intel(R) Core(TM) i7-9750H CPU @ 2.60GHz
    Memory: 5.88 GB / 32.00 GB
  Binaries:
    Node: 16.8.0 - /usr/local/bin/node
    npm: 7.21.0 - /usr/local/bin/npm
  Browsers:
    Chrome: 92.0.4515.159
    Firefox: 91.0.2
    Safari: 14.1.2
  Packages:
    html-webpack-plugin: ^5.3.2 => 5.3.2 
    webpack: ^5.52.0 => 5.52.0 
    webpack-cli: ^4.8.0 => 4.8.0 
    webpack-dev-server: ^4.1.0 => 4.1.0 

Expected Behavior

I’m expecting the page not to reload infinitely. If my configuration is not correct, I would like for webpack to tell me that in some way.

Actual Behavior

The page reloads in an infinite loop. I could extract the console output from Firefox. The following output is the only output in the console and happens before the reload is triggered:

[HMR] Cannot find update. Need to do a full reload! log.js:26:12
[HMR] (Probably because of restarting the webpack-dev-server) log.js:26:12

Important

It is important to note that this behaviour is not triggered in 100% of the cases. For me it roughly triggers in 1/3 of the cases, when using a more complex configuration (in the project I encountered this in), it’s almost every time).

For Bugs; How can we reproduce the behavior?

Please see https://github.com/chmanie/webpack-hmr-bug to find information on how to reproduce the bug (it’s quite easy).

For Features; What is the motivation and/or use-case for the feature?