Examine source code of Previews (For Twitch & YouTube & Kick)

{
  "manifest_version": 2,
  "name": "__MSG_appName__",
  "description": "__MSG_appDesc__",
  "author": "Mark M <https://previews-app.com/>",
  "homepage_url": "https://previews-app.com/",
  "default_locale": "en",
  "version": "19.0",
  "permissions": [
    "storage",
    "scripting",
    "*://*.twitch.tv/*",
    "*://*.youtube.com/*",
    "*://previews-app.com/*"
  ],
  "optional_permissions": [
    "*://kick.com/*",
    "*://*.kick.com/*",
    "cookies"
  ],
  "background": {
    "scripts": [
      "main/background.js"
    ],
    "persistent": false
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.twitch.tv/*"
      ],
      "css": [
        "main/css.css",
        "main/settings.css",
        "main/APS_settings.css"
      ],
      "js": [
        "main/tp_life.js",
        "main/core.js"
      ],
      "run_at": "document_start",
      "all_frames": true
    },
    {
      "matches": [
        "https://www.youtube.com/*"
      ],
      "exclude_matches": [
        "https://www.youtube.com/embed*",
        "https://www.youtube.com/live_chat*"
      ],
      "css": [
        "main/css.css",
        "main/settings.css"
      ],
      "js": [
        "main/tp_life.js",
        "main/core_yt.js"
      ],
      "run_at": "document_start",
      "all_frames": true
    },
    {
      "matches": [
        "https://www.youtube.com/live_chat*"
      ],
      "css": [
        "main/css.css",
        "main/css_yt_chat.css"
      ],
      "js": [
        "main/tp_life.js",
        "main/core_yt_chat.js"
      ],
      "run_at": "document_start",
      "all_frames": true
    },
    {
      "matches": [
        "https://player.twitch.tv/*channel=*"
      ],
      "js": [
        "main/core_ttv_player.js"
      ],
      "css": [
        "main/core_ttv_player.css"
      ],
      "run_at": "document_end",
      "all_frames": true
    },
    {
      "matches": [
        "https://www.youtube.com/embed*"
      ],
      "exclude_matches": [
        "https://www.youtube.com/embed*controls=0*"
      ],
      "js": [
        "main/core_yt_player.js"
      ],
      "css": [
        "main/css.css"
      ],
      "run_at": "document_start",
      "all_frames": true
    },
    {
      "matches": [
        "https://www.youtube.com/embed*"
      ],
      "exclude_matches": [
        "https://www.youtube.com/embed*controls=1*"
      ],
      "js": [
        "main/core_yt_player_preview.js"
      ],
      "run_at": "document_start",
      "all_frames": true
    },
    {
      "matches": [
        "https://clips.twitch.tv/*"
      ],
      "css": [
        "main/cd.css",
        "main/css.css"
      ],
      "js": [
        "main/cd.js"
      ],
      "run_at": "document_start",
      "all_frames": true
    },
    {
      "matches": [
        "https://previews-app.com/login*"
      ],
      "js": [
        "main/sub_login.js"
      ],
      "run_at": "document_start",
      "all_frames": true
    },
    {
      "matches": [
        "https://previews-app.com/account*"
      ],
      "js": [
        "main/sub_account.js"
      ],
      "run_at": "document_idle",
      "all_frames": true
    },
    {
      "matches": [
        "https://previews-app.com/subscribe*"
      ],
      "js": [
        "main/sub_website_subscribe.js"
      ],
      "run_at": "document_start",
      "all_frames": true
    },
    {
      "matches": [
        "https://previews-app.com/multi-stream-share*",
        "https://previews-app.com/multi-stream-layout-share*"
      ],
      "js": [
        "main/ms_share_link.js"
      ],
      "run_at": "document_idle",
      "all_frames": false
    }
  ],
  "icons": {
    "16": "images/TP16.png",
    "24": "images/TP24.png",
    "32": "images/TP32.png",
    "48": "images/TP48.png",
    "64": "images/TP64.png",
    "128": "images/TP128.png"
  },
  "browser_action": {
    "default_icon": "images/TP48.png",
    "default_title": "Previews (For Twitch & YouTube & Kick)",
    "default_popup": "popups/popup.html"
  },
  "web_accessible_resources": [
    "images/*",
    "main/*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{57340fce-fbfc-47ff-a91c-5d378b5d0dd6}"
    }
  }
}