Examine source code of Font & Color Inspector

{
  "manifest_version": 3,
  "name": "__MSG_appName__",
  "description": "__MSG_appDesc__",
  "version": "1.0.0",
  "icons": {
    "16": "icon/inactive-16.png",
    "32": "icon/inactive-32.png",
    "48": "icon/inactive-48.png",
    "128": "icon/inactive-128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "font-color-inspector@browser-extensions.dev",
      "strict_min_version": "109.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "default_locale": "en",
  "permissions": [
    "storage",
    "activeTab",
    "scripting",
    "clipboardWrite"
  ],
  "host_permissions": [
    "<all_urls>",
    "https://extensionpay.com/*"
  ],
  "action": {
    "default_title": "__MSG_appName__",
    "default_icon": {
      "16": "icon/inactive-16.png",
      "32": "icon/inactive-32.png",
      "48": "icon/inactive-48.png",
      "128": "icon/inactive-128.png"
    },
    "default_popup": "popup.html"
  },
  "commands": {
    "toggle-inspector": {
      "suggested_key": {
        "default": "Alt+Shift+F",
        "mac": "Alt+Shift+F"
      },
      "description": "__MSG_shortcutToggleDesc__"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "options_ui": {
    "open_in_tab": false,
    "page": "options.html"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "all_frames": false,
      "run_at": "document_idle",
      "js": [
        "content-scripts/content.js"
      ]
    },
    {
      "matches": [
        "https://extensionpay.com/*"
      ],
      "run_at": "document_start",
      "js": [
        "content-scripts/extpay.js"
      ]
    }
  ]
}