Examine source code of Accessibility Helper

{
  "manifest_version": 2,
  "name": "Accessibility Helper",
  "version": "1.0",
  "description": "Provides color blindness correction, text resizing, high contrast mode, and text-to-speech features",
  "icons": {
    "48": "icons/logo.svg",
    "96": "icons/logo.svg"
  },
  "permissions": [
    "activeTab",
    "storage",
    "tabs",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background/background.js"
    ],
    "persistent": false
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "libs/color-blind.js",
        "content_scripts/accessibility.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "browser_action": {
    "default_icon": {
      "48": "icons/logo.svg",
      "96": "icons/logo.svg"
    },
    "default_title": "Accessibility Helper",
    "default_popup": "popup/popup.html"
  },
  "options_ui": {
    "page": "options/options.html",
    "browser_style": true
  },
  "commands": {
    "_execute_browser_action": {
      "suggested_key": {
        "default": "Alt+A"
      },
      "description": "Open the Accessibility Helper popup"
    },
    "toggle_high_contrast": {
      "suggested_key": {
        "default": "Alt+C"
      },
      "description": "Toggle high contrast mode"
    },
    "increase_text_size": {
      "suggested_key": {
        "default": "Alt+Period"
      },
      "description": "Increase text size"
    },
    "decrease_text_size": {
      "suggested_key": {
        "default": "Alt+Comma"
      },
      "description": "Decrease text size"
    },
    "read_page": {
      "suggested_key": {
        "default": "Alt+R"
      },
      "description": "Read the current page"
    },
    "stop_reading": {
      "suggested_key": {
        "default": "Alt+S"
      },
      "description": "Stop reading"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{17a13e3c-d0e2-4abb-baf2-7d16465973b0}"
    }
  }
}