Examine source code of KaiOS Keyboard

{
  "manifest_version": 2,
  "name": "KaiOS Keyboard",
  "author": "Dylan Staley",
  "homepage_url": "https://github.com/dstaley/kaios-keyboard",
  "description": "A virtual on-screen keyboard that simulates KaiOS devices.",
  "version": "1.2",
  "icons": {
    "32": "icons/icon_32.png",
    "48": "icons/icon_48.png",
    "64": "icons/icon_64.png",
    "96": "icons/icon_96.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "permissions": [
    "tabs",
    "contextMenus"
  ]
}