Examine source code of Erev2 Night Mode

{
  "manifest_version": 2,
  "name": "Erev2 Night Mode",
  "version": "1.0.5resigned1",
  "icons": {
    "48": "favicon.png"
  },
  "description": "Erev2 theme",
  "web_accessible_resources": [
    "off.png",
    "on.png",
    "citizen.png",
    "bg.jpg",
    "bg_mu.png",
    "bg_dt.png",
    "blue_beauty_span.png",
    "elections.png",
    "employees.png",
    "checked-checkbox.png",
    "employee_on.png",
    "employee_off.png",
    "congress_off.png",
    "congress_on.png",
    "law1.png",
    "law2.png",
    "party.png",
    "congress.png",
    "president.png",
    "battle.jpg"
  ],
  "content_scripts": [
    {
      "css": [
        "styles.css"
      ],
      "js": [
        "jquery-3.3.1.min.js",
        "content.js"
      ],
      "matches": [
        "https://www.erev2.com/*"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{b0a006fd-9129-4422-ae0d-55a6b0041b39}"
    }
  }
}