Examine source code of MuteDeck

{
  "name": "MuteDeck",
  "version": "6.2.0",
  "description": "Control Google Meet, Zoom, Microsoft Teams, Jitsi, Gather, Whereby, and more with MuteDeck. Also get the app from mutedeck.com",
  "manifest_version": 3,
  "permissions": [
    "storage",
    "activeTab",
    "tabs",
    "scripting"
  ],
  "host_permissions": [
    "https://meet.google.com/*",
    "https://app.zoom.us/*",
    "https://teams.microsoft.com/*",
    "https://teams.microsoft.com.mcas.ms/*",
    "https://streamyard.com/*",
    "https://riverside.fm/*",
    "https://riverside.com/*",
    "https://meet.jit.si/*",
    "https://app.v2.gather.town/*",
    "https://whereby.com/*",
    "https://teams.cloud.microsoft/*",
    "https://*.adobeconnect.com/*"
  ],
  "optional_host_permissions": [
    "https://*/*",
    "http://*/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "https://meet.google.com/*",
        "https://app.zoom.us/*",
        "https://teams.microsoft.com/*",
        "https://teams.microsoft.com.mcas.ms/*",
        "https://streamyard.com/*",
        "https://riverside.fm/*",
        "https://riverside.com/*",
        "https://meet.jit.si/*",
        "https://app.v2.gather.town/*",
        "https://whereby.com/*",
        "https://teams.cloud.microsoft/*",
        "https://*.adobeconnect.com/*"
      ],
      "js": [
        "lib/toast.js",
        "observers/googleMeetObserver.js",
        "observers/zoomObserver.js",
        "observers/teamsObserver.js",
        "observers/streamyardObserver.js",
        "observers/riversideObserver.js",
        "observers/jitsiObserver.js",
        "observers/gatherTownObserver.js",
        "observers/wherebyObserver.js",
        "observers/adobeConnectObserver.js",
        "contentScript.js"
      ],
      "run_at": "document_start"
    }
  ],
  "background": {
    "scripts": [
      "background/reconnectingWebsocket.js",
      "background/mutedeckConnection.js",
      "background/background.js"
    ]
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": false
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "firefox@mutedeck.com"
    }
  },
  "action": {
    "default_icon": {
      "16": "images/logo-16.png",
      "32": "images/logo-32.png",
      "48": "images/logo-48.png",
      "128": "images/logo-128.png"
    },
    "default_popup": "popup.html"
  },
  "icons": {
    "16": "images/logo-16.png",
    "32": "images/logo-32.png",
    "48": "images/logo-48.png",
    "128": "images/logo-128.png"
  }
}