Examine source code of Peek Pop: Link Preview

{
  "manifest_version": 2,
  "name": "__MSG_extensionName__",
  "description": "__MSG_extensionDescription__",
  "version": "1.2.11",
  "default_locale": "en",
  "icons": {
    "48": "icon.svg",
    "96": "icon.svg",
    "128": "icon.svg"
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false,
    "type": "module"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_start",
      "match_about_blank": true,
      "all_frames": true
    }
  ],
  "permissions": [
    "contextMenus",
    "storage",
    "tabs",
    "cookies",
    "*://*/*"
  ],
  "commands": {
    "_execute_browser_action": {
      "suggested_key": {
        "default": "Alt+U",
        "mac": "MacCtrl+U"
      },
      "description": "__MSG_popAction__"
    },
    "clickModeToggle": {
      "suggested_key": {},
      "description": "__MSG_clickModeToggle__"
    }
  },
  "browser_action": {
    "default_icon": {
      "16": "icon.svg",
      "32": "icon.svg"
    },
    "default_popup": "action/action.html"
  },
  "options_ui": {
    "page": "options/options.html",
    "open_in_tab": false
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "drag_to_privew@uxer",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}