Examine source code of vvz-coursereview

{
  "manifest_version": 2,
  "description": "Better user experience on vvz.ethz.ch Features: Keep Search, Timetable Creator, filter by grading, Ratings from CourseReview",
  "name": "vvz-coursereview",
  "version": "1.6.9",
  "browser_action": {
    "default_popup": "popup.html"
  },
  "permissions": [
    "cookies",
    "https://rubberducky.vsos.ethz.ch/*",
    "https://cr.vsos.ethz.ch/*",
    "https://vvz.ethz.ch/*",
    "https://vorlesungen.ethz.ch/*",
    "https://www.vvz.ethz.ch/*",
    "https://www.vorlesungen.ethz.ch/*",
    "https://www.red9.ethz.ch/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "icons": {
    "48": "icon.svg",
    "96": "icon.svg",
    "128": "icon.svg"
  },
  "content_scripts": [
    {
      "matches": [
        "https://vvz.ethz.ch/*",
        "https://vorlesungen.ethz.ch/*",
        "https://www.vvz.ethz.ch/*",
        "https://www.vorlesungen.ethz.ch/*"
      ],
      "js": [
        "helper.js",
        "coursereview-links.js",
        "rating.js",
        "timetable.js",
        "filter.js",
        "autofill.js",
        "show_more_info.js",
        "find_old.js",
        "page-editor.js",
        "all-button.js"
      ]
    },
    {
      "matches": [
        "https://www.red9.ethz.ch/*"
      ],
      "js": [
        "on_error.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{64a9abc5-b0dd-4855-831c-7b73290c0613}"
    }
  }
}