TypeError: Cannot read properties of undefined (reading 'options') on Rsbuild

[2dragonly]

Steps to reproduce

import {
  type EnvironmentConfig,
} from "@rsbuild/core";
import imagemin from "unplugin-imagemin";

//config code, here...

const webConfig: EnvironmentConfig = {
        html: { template: config.htmlTemplate },
        source: { entry: { index: config.entry } },
        output: {
          target: "web",
          polyfill: "usage",
          legalComments: "none",
          assetPrefix: process.env?.VERCEL_PROJECT_PRODUCTION_URL
            ? `https://${process.env.VERCEL_PROJECT_PRODUCTION_URL}`
            : "/",
          distPath: {
            root: config.output.distPath,
            svg: "static/img",
            image: "static/img",
          },
          minify: config.isProdBuild,
          sourceMap: !config.isProdBuild,
          filename: config.isProdBuild
            ? {
                js: "[name].[contenthash:8].js",
                css: "[name].[contenthash:8].css",
                font: "[name][ext]",
                image: "[name].[contenthash:8][ext]",
                svg: "[name].[contenthash:8][ext]",
                assets: "[name].[contenthash:8][ext]",
              }
            : {
                js: "[name].js",
                css: "[name].css",
                font: "[name][ext]",
                image: "[name][ext]",
                svg: "[name][ext]",
                assets: "[name][ext]",
              },
        },
        performance: {
          removeConsole: config.isProdBuild,
          chunkSplit: {
            strategy: "custom",
            splitChunks: {
              chunks: "all",
              minChunks: 1,
              cacheGroups: {
                vendor: {
                  test: /[\\/]node_modules[\\/]/,
                  name: "lib-vendors",
                  chunks: "all",
                  priority: 10,
                  reuseExistingChunk: true,
                },
                react: {
                  test: /node_modules[\\/](?:react|react-dom|scheduler|react-refresh)[\\/]/,
                  name: "lib-react",
                  chunks: "all",
                  priority: 20,
                },
                router: {
                  test: /node_modules[\\/](?:react-router|react-router-dom|history|@remix-run[\\/]router)[\\/]/,
                  name: "lib-router",
                  chunks: "all",
                  priority: 20,
                },
                utils: {
                  name: "lib-common",
                  minChunks: 2,
                  chunks: "all",
                  priority: 5,
                  reuseExistingChunk: true,
                },
              },
            },
          },
          preload: {
            type: "all-chunks",
          },
          prefetch: {
            type: "all-chunks",
          },
        },
        tools: {
          rspack(_config, utils) {

            _config.plugins ??= [];
            _config.plugins.push(imagemin.webpack({}))
          },
        },
      };

rsbuild dev or rsbuild build

What is expected?

successfully compressed images

What is actually happening?

Rsbuild v1.7.3

start   build started...
TypeError: Cannot read properties of undefined (reading 'options')
    at Context.generateDefaultValue (file:///Users/2dragonly/Documents/Projects/kfsdu931/node_modules/unplugin-imagemin/dist/chunk-NJT32BLA.mjs:1246:69)
    at Context.loadBundleHook (file:///Users/2dragonly/Documents/Projects/kfsdu931/node_modules/unplugin-imagemin/dist/chunk-NJT32BLA.mjs:1142:25)

System Info

System:
    OS: macOS 26.3
    CPU: (10) arm64 Apple M2 Pro
    Memory: 1.89 GB / 16.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 25.6.0 - /opt/homebrew/bin/node
    Yarn: 1.22.22 - /usr/local/bin/yarn
    npm: 11.8.0 - /opt/homebrew/bin/npm
    pnpm: 10.28.0 - /usr/local/bin/pnpm
    bun: 1.3.5 - /Users/lazuee/.bun/bin/bun
  Browsers:
    Chrome: 144.0.7559.110
    Safari: 26.3
  npmPackages:
    @babel/preset-env: ^7.29.0 => 7.29.0 
    @babel/preset-react: ^7.28.5 => 7.28.5 
    @rsbuild/core: ^1.7.3 => 1.7.3 
    @rsbuild/plugin-babel: ^1.1.0 => 1.1.0 
    @rsbuild/plugin-react: ^1.4.5 => 1.4.5 
    react: ^19.2.4 => 19.2.4 
    react-dom: ^19.2.4 => 19.2.4 
    react-router: ^7.13.0 => 7.13.0 
    unplugin-imagemin: ^0.7.0 => 0.7.0

Any additional comments?

No response