WebView2 Evergreen installer no longer adds the registry key recommended for detection

[psycholns]

Description
To verify that the webview2 runtime is installed we check (as recommended in https://docs.microsoft.com/en-us/microsoft-edge/webview2/concepts/distribution) the registry key at:
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\EdgeUpdate\Clients{F3017226-FE2A-4295-8BDF-00C3A9A7E4C5}

This has worked so far, but now, if uninstalling the webview2 component and installing it again won't add that key, and therefore our users without the runtime end up in a (manual) install loop.

Verified on 2 machines so far. And looking at our logs it seems to have been an issue since around the 3rd (no errors from installer, but no runtime detected afterwards either).

Version
Runtime: 96.0.1054.53
OS: Win10, 19043
(SDK: 1.0.992.28)
(Framework: WinForms)

Repro Steps

1. Observe HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\EdgeUpdate\Clients{F3017226-FE2A-4295-8BDF-00C3A9A7E4C5} being present
2. Uninstall Microsoft Edge WebView2 Runtime
3. Now the registry key is gone (as expected)
4. Install Microsoft Edge WebView2Runtime from https://developer.microsoft.com/en-us/microsoft-edge/webview2/#download-section (evergreen bootstrapper)
5. The registry key is still missing

AB#37397652

[psycholns]

After further digging around in the registry I figured out that the runtime is now per-user installed (which is great news for our otherwise user installed app!) and thus the key is available here instead:
HKCU\SOFTWARE\Microsoft\EdgeUpdate\Clients{F3017226-FE2A-4295-8BDF-00C3A9A7E4C5}

So now it's just a problem for existing software out there and the documentation.

[jasonstephen15]

Thank @psycholns for the post! @liminzhu made a post about it here: MicrosoftEdge/WebView2Announcements#37. But I agree we should have better permanent documentation about this. I will open an item to update the docs! Let me know if you have any other questions.

[Fowlox]

It is necessary to change from checking hard coded registry path to another way.
Recommend to verifying the runtime installed in the following way.

In .NET based framework (In my case, WPF)

var clientInstalled = true;
try
{
    var version = CoreWebView2Environment.GetAvailableBrowserVersionString();
}
catch (WebView2RuntimeNotFoundException)
{
    clientInstalled = false;
}

In WIN32 platform,

Call GetAvailableCoreWebView2BrowserVersionString(PCWSTR browserExecutableFolder, LPWSTR * versionInfo) and check whether the versionInfo is NULL. If versionInfo is NULL, the WebView2 Runtime isn't currently installed on the client.

I haven't tried this way, but it has been mentioned by Distribute a WebView2 app and the WebView2 Runtime.

[ywmluclt]

I stucked at it in a while. pleaseeeeee update the document

[ywmluclt]

I just checked it again and I realized that:

• If you install WebView2 Runtime manually (download into local and setup by double click on MicrosoftEdgeWebview2Setup.exe), then the key is available at HKCU\SOFTWARE\Microsoft\EdgeUpdate\Clients{F3017226-FE2A-4295-8BDF-00C3A9A7E4C5}
• If you install WebView2 Runtime by command. In my case, I installed it from NSIS file setup, then the key is available at HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\EdgeUpdate\Clients{F3017226-FE2A-4295-8BDF-00C3A9A7E4C5}:

Function installWebView2
	ClearErrors
	ReadRegStr $0 HKLM "SOFTWARE\WOW6432Node\Microsoft\EdgeUpdate\Clients\{F3017226-FE2A-4295-8BDF-00C3A9A7E4C5}" "pv"
	${If} ${Errors} 
	${OrIf} $0 == ""
		DetailPrint "Dowloading: WebView2 Runtime"		
		InetLoad::load "http://go.microsoft.com/fwlink/p/?LinkId=2124703" "$TEMP\MicrosoftEdgeWebview2Setup.exe"
        Pop $R0
		StrCmp $R0 "OK" OK
			MessageBox MB_OK|MB_ICONEXCLAMATION "Failed to download WebView2 Runtime. ${PRODUCT_NAME} will continue to install, but the Map in ${PRODUCT_NAME} will not run properly without WebView2 Runtime. You must install WebView2 Runtime manually."
			Goto done_installWebView2_function
        OK:
		DetailPrint "Installing: WebView2 Runtime"
		ExecWait '"$TEMP\MicrosoftEdgeWebview2Setup.exe" /silent /install'
	${EndIf}
	done_installWebView2_function:
FunctionEnd

Just share my experience