recently in learning webpack4, I don"t know much about the newly added optimization. I wrote a demo, according to online learning, but I didn"t expect the result. Ask God for help to see what the problem is

package.json:

{
    "name": "test",
    "version": "1.0.0",
    "description": "",
    "main": "index.js",
    "scripts": {
        "test": "echo \"Error: no test specified\" && exit 1"
    },
    "author": "",
    "license": "ISC",
    "devDependencies": {
        "webpack": "^4.15.1",
        "webpack-cli": "^3.1.0"
    },
    "dependencies": {
        "lodash": "^4.17.10"
    }
}

module.js:

export default "module";

subPageA.js:

import "./module.js";
export default "subPageA";

subPageB.js:

import "./module.js";
export default "subPageB";

pageA.js:

import "./subPageA.js";
import "./subPageB.js";

import * as _ from "lodash";
console.log("At page "A" :", _);

export default "pageA";

pageB.js:

import "./subPageA.js";
import "./subPageB.js";

import * as _ from "lodash";
console.log("At page "B" :", _);

export default "pageB";

webpack.config.js:

const path = require("path");
const webpack = require("webpack");

module.exports = {
    entry: {
        pageA: "./src/pageA.js",
        pageB: "./src/pageB.js"
    },
    output: {
        filename: "[name].bundle.js",
        path: path.resolve(__dirname, "dist"),
        chunkFilename: "[name].chunk.js"
    },
    optimization: {
        splitChunks: {
            cacheGroups: { 
                commons: {
                    name: "commons",
                    chunks: "all", 
                    minChunks: 2,
                    priority: 0 
                },
                vendor: { 
                    name: "vendor",
                    test: /[\\/]node_modules[\\/]/,
                    chunks: "all", 
                    priority: 10 
                }
            }
        }
    }
};

is to generate a commons.chunk.js, that contains repeatedly introduced custom modules, and a vendor.chunk.js module that contains node_modules, that is, the lodash module, but the actual generation is:

what is wrong with my configuration or misunderstanding? (minChunks is set to 1 or 2 to all or other values have been tried, and the result is the same)