Examine source code of Slack Beeegmojis

{
  "manifest_version": 2,
  "name": "Slack Beeegmojis",
  "version": "0.13.0",
  "description": "Makes emojis in Slack bigger so you can actually appreciate them.",
  "homepage_url": "https://github.com/atl-mk/slack-beeegmojis",
  "icons": {
    "32": "icon32.png",
    "48": "icon48.png",
    "64": "icon64.png",
    "128": "icon128.png",
    "512": "icon512.png"
  },
  "browser_action": {
    "browser_style": true,
    "default_title": "Slack Beeegmojis",
    "default_popup": "extension-popup.html",
    "default_icon": {
      "32": "icon32.png",
      "48": "icon48.png",
      "64": "icon64.png",
      "128": "icon128.png",
      "512": "icon512.png"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "*://app.slack.com/client/*"
      ],
      "js": [
        "browser-polyfill.min.js",
        "extension-change-size.js"
      ]
    }
  ],
  "permissions": [
    "*://app.slack.com/client/*",
    "storage"
  ],
  "web_accessible_resources": [
    "*.css"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{26b99005-860e-4ad3-8599-b4a7fc54284c}"
    }
  }
}