[Problem/Bug]: Enabling AllowHostInputProcessing "breaks" "open with" window

[Bjoern76]

What happened?

If I enable AllowHostInputProcessing and then click on any link that would open an "open with" window, the window will open in the background with its own taskbar entry instead of as top window without taskbar entry. As soon as I click on the "open with" taskbar entry it vanishes.

This happens only when starting the app without debugger.

The issue is easily reproduced using the WebView2APISample app without any code changes (see below).

It happens at least with mailto and tel links but I guess it will happen with any kind of link that will cause the "open with" window to open.

I don't have this issue when AllowHostInputProcessing is set to false.

Importance

Moderate. My app's user experience is affected, but still usable.

Runtime Channel

Stable release (WebView2 Runtime)

Runtime Version

145.0.3800.70

SDK Version

1.0.3848.0

Framework

Win32

Operating System

Windows 11

OS Version

10.0.26200

Repro steps

• Start the WebView2APISample app without debugger.
• Select "Windowed - HostInputProcessing" as "WebView Creation Mode". and recreate the WebView.
• Navigate to e.g. https://www.w3schools.com/tags/tryit.asp?filename=tryhtml_link_mailto and click on the mailto link.

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