Nadella calls Copilot an OS again, but it's a Chromium web app on Windows 11

Satya Nadella again described Copilot as a "new OS for work" in a leadership update. A Windows Latest teardown shows copilotapp.exe is a rebranded Edge launcher bundling a full Chromium build (~520MB), with a small WinUI host handling only voice, screen capture and the floating overlay.

• copilotapp.exe is 4.99MB and imports the same DLLs as Edge
• A full Edge 154 build of ~520MB sits alongside it, including a 349.6MB msedge.dll
• The native WinUI host on .NET 10 only handles voice and screen capture
• Home, Code, Autopilot and Today are not yet available in the app