[Problem/Bug]: Visual hosting (DComp) text becomes blurry/dim when taskbar thumbnail is shown; recovers on activation

[xystar2012]

What happened?

In our Win32 app using WebView2 visual hosting (DirectComposition), text inside the WebView becomes blurry/dim when hovering the app icon on the Windows taskbar (taskbar thumbnail / live preview appears).
When the WebView/window is activated again, text clarity returns to normal immediately.
This does not happen in our windowed hosting mode.

Importance

Important. My app's user experience is significantly compromised.

Runtime Channel

Stable release (WebView2 Runtime)

Runtime Version

No response

SDK Version

No response

Framework

Win32

Operating System

Windows 11

OS Version

Windows 11 (10.0.26200)

Repro steps

1. Create WebView2 in visual hosting (DComp) mode.
2. Show a static text-heavy page (non-animated text content).
3. Hover app icon on taskbar so thumbnail/live preview appears.
4. Observe text in the main WebView area becomes blurry/dim.
5. Activate the WebView/window (click/focus), text returns to normal.

Repros in Edge Browser

No, issue does not reproduce in the corresponding Edge version

Regression

No, this never worked

Last working version (if regression)

No response