Getting "window is not defined" in client/overlay.js after upgrading to webpack-dev-server 4.12

[cakoose]

Bug report

1. I have a tiny repo that uses webpack-dev-server.
2. I use webpack serve and view the page in a browser.
3. This works fine with webpack-dev-server 4.11.1. But when I upgrade to 4.12, I get an error page.

Actual Behavior

With 4.12, I get an error page:

Uncaught ReferenceError: window is not defined
    at eval (webpack://monaco-utf8-length-incremental/./node_modules/webpack-dev-server/client/overlay.js?:247:56)

Screenshot:

Expected Behavior

With 4.11.1, the expected page loads. It's a page with the Monaco text editor that shows a character count at the bottom.

How Do We Reproduce?

To get the expected behavior (webpack-dev-server 4.11.1):

1. git clone https://github.com/cakoose/monaco-utf8-length-incremental
2. git checkout 8ed7c9430db129788418dc20f4a39eb089164c14
3. yarn run start
4. Point your browser at http://localhost:8080
5. See that the page loads

To the the error behavior (webpack-dev-server 4.12):

6. Edit "package.json" and edit the "webpack-dev-server" depenency from "4.11.1" to "4.12"
7. yarn install
8. yarn run start
9. Point your browser at http://localhost:8080
10. See the error page.

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

System:
  OS: macOS 12.6.3
  CPU: (12) x64 Intel(R) Core(TM) i7-9750H CPU @ 2.60GHz
  Memory: 256.44 MB / 32.00 GB
Binaries:
  Node: 18.14.1 - ~/.volta/tools/image/node/18.14.1/bin/node
  Yarn: 3.4.1 - ~/.volta/tools/image/yarn/1.22.19/bin/yarn
  npm: 9.3.1 - ~/.volta/tools/image/node/18.14.1/bin/npm
Browsers:
  Chrome: 111.0.5563.64
  Edge: 111.0.1661.44
  Firefox: 111.0
  Safari: 16.3
Packages:
  css-loader: 6.7.3 => 6.7.3
  file-loader: 6.2.0 => 6.2.0
  html-webpack-plugin: 5.5.0 => 5.5.0
  style-loader: 3.3.2 => 3.3.2
  ts-loader: 9.4.2 => 9.4.2
  webpack: 5.76.2 => 5.76.2
  webpack-cli: 5.0.1 => 5.0.1
  webpack-dev-server: 4.12.0 => 4.12.0

[alexander-akait]

Yeah, good catch, @malcolm-kee fix is easy, if no document.window do nothing, why it happens - some applications have workers and don't exclude dev server client for entries (because it requires more setup), but it is not critical because it is just dev env, so to avoid it let's do nothing

[alexander-akait]

@cakoose Will fix in near future

[cakoose]

Glad to hear that there's an easy fix!

Separately, I was curious about this comment:

some applications have workers and don't exclude dev server client for entries (because it requires more setup)

Is there some setup I can do to be more "correct"?

[jagribble]

Also getting this issue.

don't exclude dev server client for entries (because it requires more setup)

Is there an example of this setup?