Stealth Mode: how CueNova stays off a shared screen

What Stealth Mode actually does

Windows exposes a per-window flag that tells the compositor to omit a window from the frames it hands to screen-capture APIs. CueNova sets that flag on its overlay. The window stays fully visible on your own physical display, drawn by your GPU as normal, but the buffer a capturing application receives has the overlay composited out of it.

This is an operating-system feature, not a trick played on the conferencing app. CueNova is not injecting into Zoom, patching Teams, or intercepting a video stream. It sets a documented flag on its own window and Windows honours it at the compositor level. That distinction matters: there is nothing for a conferencing client to detect in its own process, because nothing was done to it.

The practical result is that when a supported screen share captures your desktop, the interviewer sees your desktop as it would look with CueNova closed. Your browser, your editor, your slides — everything except the overlay panel.

Capture paths Stealth Mode covers

Screen sharing is not one technology. Different applications capture the screen in different ways, and capture exclusion applies to the paths that route through the Windows compositor.

• Windows Graphics Capture

  The modern capture API used by current builds of the major conferencing clients for window and desktop sharing. Capture exclusion is honoured here.

• Desktop Duplication

  The older full-desktop capture path still used by some clients and recorders. Exclusion is honoured on compositor-level capture.

• Browser tab and window sharing

  Screen sharing initiated from inside a browser — a Meet call in Chrome, for example — routes through the same OS picker and the same compositor.

• Common desktop recorders

  Recording tools that capture through the standard Windows APIs receive the same composited-out frames a live share does.

Where Stealth Mode does not apply

This is the part most pages in this category leave out. Read it before you rely on the feature — the honest boundary is short, and knowing it is what makes the tool usable.

• A second camera pointed at your screen

  Capture exclusion is a property of the frame buffer. A phone or webcam physically filming your monitor records photons, not buffers, and sees whatever your eyes see.

• Remote-control and proctoring agents

  Software that takes over the machine or runs with elevated privileges to inventory processes is a different category of observation entirely. Locked-down proctored assessments are not a supported use case.

• Hardware capture devices

  An HDMI capture card sits downstream of the compositor and receives the finished signal sent to the display.

• Unsupported or changed capture methods

  Applications update. A client that honours the flag today may adopt a different capture path in a future release. This is why the setup check below exists.

Verify Stealth Mode on your own setup in three minutes

Never trust a stealth feature you have not tested on the exact machine, the exact app version and the exact share mode you plan to use. Do this once, before it matters.

1. Start a call with yourself

   Open your conferencing app and start a meeting with no other participants. Every major client allows a solo meeting.

2. Share the way you will actually share

   If the interviewer will ask for your entire screen, share your entire screen. Window-only and desktop sharing take different capture paths, so test the one you will use.

3. Join from a second device

   Open the same meeting on your phone as a second participant and look at the shared view. This is precisely what the interviewer will see.

4. Confirm, then leave the setup alone

   The overlay should be absent from the phone view and present on your desktop. If your conferencing client later prompts for a major update, re-run this check.

Why "guaranteed undetectable" is a claim worth distrusting

Any product in this category that promises unconditional invisibility is describing something software cannot deliver. Capture exclusion depends on how the other application chooses to capture, and that is outside any vendor's control. A tool that tells you otherwise has either not thought about it or has decided the sale matters more than your interview.

CueNova states the mechanism and its limits and gives you a three-minute test to confirm it on your own hardware. That is a stronger position than a promise: you leave the check knowing what your setup does, rather than hoping.