title: error NG6002: Appears in the NgModule.imports of <module>, but could not be resolved to an NgModule class
body: <p>I just updated from Angular 8.2 to 9.</p>
  
  <p>Everything works well if I disable ivy, but when it's enabled I'm getting a lot of errors that seems to be kind of obscure, at least I can't find any results when googling it.</p>
  
  <p>I'm quite sure I've done everything needed for an update, i.e. changed the lazyloading to use dynamic imports and fixed Angular Material import paths etc.</p>
  
  <p>I will also include my <em>package.json</em> dependencies here</p>
  
  <pre><code>  "dependencies": {
      "@angular/animations": "^9.0.0",
      "@angular/cdk": "^9.0.0",
      "@angular/common": "^9.0.0",
      "@angular/compiler": "^9.0.0",
      "@angular/core": "^9.0.0",
      "@angular/fire": "^5.4.2",
      "@angular/flex-layout": "^9.0.0-beta.29",
      "@angular/forms": "^9.0.0",
      "@angular/http": "^7.2.15",
      "@angular/material": "^9.0.0",
      "@angular/material-moment-adapter": "^8.2.2",
      "@angular/platform-browser": "^9.0.0",
      "@angular/platform-browser-dynamic": "^9.0.0",
      "@angular/platform-server": "^9.0.0",
      "@angular/router": "^9.0.0",
      "@ngrx/effects": "^8.3.0",
      "@ngrx/entity": "^8.3.0",
      "@ngrx/router-store": "^8.3.0",
      "@ngrx/store": "^8.3.0",
      "@zxing/ngx-scanner": "^2.0.1",
      "angular-resizable-element": "^3.2.4",
      "angular-resize-event": "^1.1.1",
      "angular2-highcharts": "^0.5.5",
      "core-js": "^3.6.4",
      "detect-browser": "^4.7.0",
      "firebase": "^7.8.0",
      "google-polyline": "^1.0.3",
      "hammerjs": "^2.0.8",
      "highcharts": "^8.0.0",
      "i18n-iso-countries": "^4.3.1",
      "leaflet": "^1.5.1",
      "mapbox-gl": "^1.4.0",
      "moment": "^2.24.0",
      "moment-timezone": "^0.5.26",
      "ng-pick-datetime": "^6.0.7",
      "ngrx-store-freeze": "^0.2.3",
      "ngx-cacheable": "^1.3.2",
      "ngx-cookie-service": "^2.2.0",
      "ngx-csv": "^0.3.1",
      "ngx-file-drop": "^8.0.8",
      "ngx-infinite-scroll": "^0.8.4",
      "papaparse": "^5.0.2",
      "request": "^2.87.0",
      "request-promise": "^4.2.2",
      "rxjs": "^6.5.4",
      "rxjs-compat": "^6.3.3",
      "typescript-string-operations": "^1.3.1",
      "web-animations-js": "^2.3.2",
      "zone.js": "^0.10.2"
    },
    "devDependencies": {
      "@angular-devkit/build-angular": "^0.900.1",
      "@angular/cli": "^9.0.0",
      "@angular/compiler-cli": "^9.0.0",
      "@angular/language-service": "^9.0.0",
      "@ngrx/store-devtools": "^8.3.0",
      "@types/body-parser": "^1.17.0",
      "@types/cors": "^2.8.4",
      "@types/detect-browser": "^4.0.0",
      "@types/express": "^4.11.1",
      "@types/firebase": "^3.2.1",
      "@types/helmet": "0.0.37",
      "@types/jasmine": "^3.5.4",
      "@types/jasminewd2": "~2.0.3",
      "@types/leaflet": "^1.2.7",
      "@types/lodash": "^4.14.109",
      "@types/node": "^13.7.1",
      "@types/request": "^2.47.0",
      "@types/request-promise": "^4.1.41",
      "codelyzer": "^5.2.1",
      "concurrently": "^3.5.1",
      "del-cli": "^1.1.0",
      "jasmine-core": "^3.5.0",
      "jasmine-spec-reporter": "^4.2.1",
      "karma": "^4.4.1",
      "karma-chrome-launcher": "^3.1.0",
      "karma-cli": "^2.0.0",
      "karma-coverage-istanbul-reporter": "~1.4.2",
      "karma-jasmine": "^3.1.1",
      "karma-jasmine-html-reporter": "^1.5.2",
      "protractor": "^5.4.3",
      "puppeteer": "^2.0.0",
      "rxjs-tslint": "^0.1.7",
      "ts-node": "~5.0.1",
      "tslint": "^6.0.0",
      "typescript": "3.6.4",
      "webpack": "^4.41.6"
    },
    "peerDependencies": {
      "typescript": "3.6.4",
      "tslib": "1.10.0"
    },
  </code></pre>
  
  <p>And errors itself that I'm getting:</p>
  
  <p><a href="https://i.stack.imgur.com/UrCIT.png" rel="noreferrer"><img src="https://i.stack.imgur.com/UrCIT.png" alt="enter image description here"></a></p>
  
  <p>I have cleared my <em>node_modules</em> and <em>package-lock.json</em> and ran <em>npm install</em> again</p>
  
  <p><strong>EDIT</strong>: maybe also important to note that it's compiling and running with <code>ng serve</code> but when I try to build it or run with AOT <code>ng serve -aot</code> then I get the errors.</p>