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TypeError: Invalid value used in weak set

See original GitHub issue

Operating System: MacOS Big Sur 11.1
Node Version: v10.16.3
NPM Version: 6.9.0
webpack Version: 4.44.2
mini-css-extract-plugin Version: 2.0.0

Expected Behavior

Npm run build succeed

Actual Behavior

TypeError: Invalid value used in weak set at WeakSet.add (<anonymous>) at MiniCssExtractPlugin.apply (/Users/grzegorztarnowski/***/***/web/node_modules/mini-css-extract-plugin/dist/index.js:362:18)

Code

webpack.common.js

https://gist.github.com/gtarnowski/8c3bd7ca346bb15af5913d586efb3fd4

package.json

https://gist.github.com/gtarnowski/828fe24c13304376677e93c0e72bdc75

How Do We Reproduce?

Error shows on npm run build process. After downgrading mini-css-extract-plugin to version 1.6.2 - error disappear. The error appears in the new version, so I report it.

Issue Analytics

State:
Created 2 years ago
Reactions:8
Comments:12 (6 by maintainers)

Top GitHub Comments

35reactions

gtarnowskicommented, Jul 3, 2021

You need webpack v5 to use the 2.0.0 version, please read the changelog before update, I really don’t understand why the developers don’t do it, it is major release so breaking changes expected

Some less experienced developers (like me) can didn’t know that changelog can include such information. But im glad that you give me a lesson in such kind way.

24reactions

alexander-akaitcommented, Jul 1, 2021

You need webpack v5 to use the 2.0.0 version, please read the changelog before update, I really don’t understand why the developers don’t do it, it is major release so breaking changes expected

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