TypeError: node.getIterator is not a function

[LP1994]

node: 14.11.0;
npm: 6.14.8;
operating system: Windows 10;
postcss: 8.0.5;
postcss-less: 3.1.4;

Error description:
ERROR in ./src/styles/less/basic/Basic.less
Module build failed (from ./node_modules/postcss-loader/dist/cjs.js):
TypeError: node.getIterator is not a function
at LazyResult.visitTick (G:\SNWS\sn-micro-front-web-project-template\node_modules\postcss\lib\lazy-result.js:470:33)
at LazyResult.runAsync (G:\SNWS\sn-micro-front-web-project-template\node_modules\postcss\lib\lazy-result.js:357:30)
at async Object.loader (G:\SNWS\sn-micro-front-web-project-template\node_modules\postcss-loader\dist\index.js:94:14)
@ ./src/tplEJS/pages/AuditLogIndex.ejs (./node_modules/html-webpack-plugin/lib/loader.js!./src/tplEJS/pages/AuditLogIndex.ejs) 83:10-42

step:
When I use the following configuration, an error will be reported: TypeError: node.getIterator is not a function.
{
test: /.less$/i,
use: [
{
loader: 'file-loader',
options: {
name: '[name]_[sha512:contenthash:hex:6].css',
outputPath: './styles/',
emitFile: true,
esModule: false,
}
},
{
loader: 'extract-loader',
},
{
loader: 'css-loader',
options: {
url: true,
import: true,
importLoaders: 2,
esModule: false,
},
},

    // If you comment out the "postcss-loader" below, you won't get an error(TypeError: node.getIterator is not a function).
    {
        loader: 'postcss-loader',
        options: {
            execute: false,
            sourceMap: false,
            postcssOptions: {
                syntax: require( 'postcss-syntax' )( {
                    css: require( 'postcss-safe-parser' ),
                    sass: require( 'postcss-sass' ),
                    scss: require( 'postcss-scss' ),
                    less: require( 'postcss-less' ),
                } ),
            },
        },
    },

    {
        loader: 'less-loader',
        options: {
            lessOptions: {
                math: 'strict-legacy',
                strictUnits: true,
                noIeCompat: true,
            },
        },
    },
],
sideEffects: true,

}

explain:
When processing ".less" files, if "postcss-loader" is not used, no error will be reported and it can be successfully compiled. If "postcss-loader" is used, an error will be reported. Moreover, the above configuration will not report an error in postcss 7. X, but it will be reported if it is updated to postcss 8. X.

[LP1994]

I live in the East eight international time zone, so if you have any questions, you may not be able to reply in time. Please forgive me for the inconvenience.

[ai]

Seems like postcss-less do not support PostCSS 8. Downgrade other PostCSS modules.

I will create an issue in postcss-less tomorrow.

[LP1994]

Thank you for your timely reply!!! At first, I thought that it might be the "postcss less" problem. However, the code reported "postcss", so I came here to submit the error. Now I will go to "postcss less" to submit this error.

[ai]

Here is a correct issue shellscape/postcss-less#150

[Juraj-Masiar]

Hello,
I'm having the same issue, but I'm not using less:

        {
          test: /\.css$/,
          use: [
            MiniCssExtractPlugin.loader,
            "css-loader",
            "postcss-loader",    // if I comment out this line, it will work again
          ]
        },

This is the full stack trace:

ERROR in ./src/editor/editor.vue?vue&type=style&index=0&lang=scss& (./node_modules/css-loader/dist/cjs.js!./node_modules/vue-loader/lib/loaders/stylePostLoader.js!./node_modules/sass-loader/dist/cjs.js!./node_modules/postcss-loader/dist/cjs.js!./node_modules/vue-loader/lib/index.js??vue-loader-options!./src/editor/editor.vue?vue&type=style&index=0&lang=scss&)
Module build failed (from ./node_modules/postcss-loader/dist/cjs.js):
TypeError: node.getIterator is not a function
    at LazyResult.visitTick (C:\Users\Juraj\git\addons\PrivateNotes\node_modules\postcss\lib\lazy-result.js:528:33)
    at LazyResult.runAsync (C:\Users\Juraj\git\addons\PrivateNotes\node_modules\postcss\lib\lazy-result.js:408:30)
    at LazyResult.async (C:\Users\Juraj\git\addons\PrivateNotes\node_modules\postcss\lib\lazy-result.js:221:30)
    at LazyResult.then (C:\Users\Juraj\git\addons\PrivateNotes\node_modules\postcss\lib\lazy-result.js:206:17)
 @ ./node_modules/vue-style-loader/index.js!./node_modules/css-loader/dist/cjs.js!./node_modules/vue-loader/lib/loaders/stylePostLoader.js!./node_modules/sass-loader/dist/cjs.js!./node_modules/postcss-loader/dist/cjs.js!./node_modules/vue-loader/lib/index.js??vue-loader-options!./src/editor/editor.vue?vue&type=style&index=0&lang=scss& 4:14-328
 @ ./src/editor/editor.vue?vue&type=style&index=0&lang=scss& 1:0-364 1:0-364
 @ ./src/editor/editor.vue 4:0-67
 @ ./src/editor/editor.ts 10:0-34 26:49-55

And my libraries:

"autoprefixer": "^10.3.1",
"html-inline-css-webpack-plugin": "^1.11.1",
"mini-css-extract-plugin": "^2.1.0",
"postcss": "^8.3.6",
"postcss-cli": "^8.3.1",
"postcss-comment": "^2.0.0",
"postcss-load-config": "^3.1.0",
"postcss-loader": "^6.1.1",
"postcss-plugin": "^1.0.0",
"sass": "^1.36.0",
"sass-loader": "^12.1.0",
"style-loader": "^3.2.1",
"vue-loader": "^15.9.6",
"vue-style-loader": "^4.1.3",

I'm trying to migrate to Webpack 5 and this is the last problem I'm facing.
I've tried to downgrade PostCSS from 8 to 7 but then I get a different error from one of the libraries that says:

Error: PostCSS plugin postcss-discard-comments requires PostCSS 8

EDIT:

So I've managed to track down the issue to the "postcss-comment" library which was not updated in 3 years :(

[latel]

postcss-comment

any ideas how to track which library is causing this issue?