Examine source code of PlainSight

{
  "name": "PlainSight",
  "version": "1.2.0",
  "description": "Send and receive messages hidden in plain sight.",
  "manifest_version": 2,
  "developer": {
    "name": "David Menear",
    "url": "https://menear.dev"
  },
  "author": "David Menear",
  "browser_specific_settings": {
    "gecko": {
      "id": "plainsight@menear.dev"
    }
  },
  "permissions": [
    "activeTab",
    "clipboardRead",
    "contextMenus",
    "storage"
  ],
  "commands": {
    "fullDecrypt": {
      "suggested_key": {
        "default": "Alt+Shift+D"
      },
      "description": "Decrypt page in active tab"
    },
    "revertPage": {
      "suggested_key": {
        "default": "Alt+Shift+R"
      },
      "description": "Revert page in active tab"
    },
    "encryptSelectedInput": {
      "suggested_key": {
        "default": "Alt+Shift+X"
      },
      "description": "Encrypt the selected text"
    },
    "_execute_browser_action": {
      "suggested_key": {
        "default": "Alt+Shift+Q"
      }
    }
  },
  "background": {
    "scripts": [
      "js/messages.js",
      "js/common.js",
      "js/aes.js",
      "js/scrypt.js",
      "js/cryptofunctions.js",
      "js/background.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "images/icon16.png",
      "32": "images/icon32.png",
      "48": "images/icon48.png",
      "128": "images/icon128.png"
    }
  },
  "icons": {
    "16": "images/icon16.png",
    "32": "images/icon32.png",
    "48": "images/icon48.png",
    "128": "images/icon128.png"
  }
}