README
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nocapture
Keeps a window's content out of screenshots, screen recordings and screen sharing: captures show the window as a black rectangle while the user keeps seeing it normally — the way DRM-locked video players appear in a shared screen.
err := nocapture.Protect(w.Window()) // e.g. a glaze WebView handle
| Platform | Backend | Effect |
|---|---|---|
| Windows | SetWindowDisplayAffinity(WDA_MONITOR) |
window blacked out in captures |
| macOS | — | ErrUnsupported (see below) |
| Linux | — | ErrUnsupported: no portable compositor API |
Why no macOS backend. The old -[NSWindow setSharingType: NSWindowSharingNone] stopped working in macOS 15.4 — ScreenCaptureKit
ignores it — Apple now documents the constant as legacy, and Apple DTS has
stated there is no public API for preventing screen capture. Worse: on
macOS 26 setting the legacy value can stop the window from rendering at all.
A backend that either does nothing or breaks the window would be worse than
an honest ErrUnsupported.
Call it from the UI thread once the window exists. The handle is the
toolkit's native window pointer (HWND), exactly what glaze's
WebView.Window() returns.
This is a privacy courtesy enforced by the OS compositor, not content DRM: it does nothing against a camera pointed at the display.
Documentation
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Overview ¶
Package nocapture keeps a window's content out of screenshots, screen recordings and screen sharing, cgo-free — captures show the window as a black rectangle while the user keeps seeing it normally, the way DRM-locked video players appear in a shared screen.
err := nocapture.Protect(w.Window()) // e.g. a glaze WebView handle
Platform truth, stated plainly:
Windows: SetWindowDisplayAffinity(WDA_MONITOR). Supported and reliable.
macOS: ErrUnsupported. The old -[NSWindow setSharingType: NSWindowSharingNone] stopped working in macOS 15.4 (ScreenCaptureKit ignores it), Apple documents the constant as legacy, and DTS has stated there is no public API for preventing screen capture. Worse, on macOS 26 the legacy value can stop the window from rendering at all, so this package refuses to set it.
Linux: ErrUnsupported. Neither X11 nor Wayland exposes a portable equivalent.
This is a privacy courtesy enforced by the OS compositor, not content DRM: it does nothing against a camera pointed at the display.
Index ¶
Constants ¶
This section is empty.
Variables ¶
var ErrUnsupported = errors.New("nocapture: not supported on this platform")
ErrUnsupported is returned on a platform with no working backend: Linux has no compositor API for it, and macOS removed the one it had (see the package comment).
Functions ¶
Types ¶
This section is empty.
Source Files