Side-by-side 32 and 64bit fixed version, 64bit stops working if 32bit has been used once

[zoli13]

Our app has both 32 and 64bit version, customer can decide which one to install (both is also possible).
We use fixed version of WebView2 Runtime (32 / 64, according to the App platorm), which is deployed together with the app.
So folder structure is like this:

32bit App, uses 32bit WebView2:
/program files(x86)
---/ourApp
------/Microsoft.WebView2.FixedVersionRuntime

64bit App, uses 64bit WebView2:
/program files
---/ourApp
------/Microsoft.WebView2.FixedVersionRuntime

If you start 64bit App first, you can use the (64bit) WebView2 in the App, works fine.
Close it, and start 32bit App. You can use the (32bit) WebView2 in the App, works fine.
Close it, and start 64bit App.
From now on, the 64bit WebView2 won't work anymore.

So it seems after starting 32bit App (which uses 32bit WebView2) the 64bit App's 64bit WebView2 just gives a gray background, does not load the page.

TaskMgr:
msedgewebview2.exe uses 100% cpu (1 core), and memory usage is increasing till ~6GB, then process closed, and another msedgewebview2.exe instance is started...forever...

Tried with
Microsoft.WebView2.FixedVersionRuntime.103.0.1264.77
Microsoft.WebView2.FixedVersionRuntime.104.0.1293.54
Microsoft.WebView2.FixedVersionRuntime.94.0.992.50

Same.

If I ever started the 32bit App (which uses 32bit fixed WebView2), the same version of the 64bit WebView2 won't work anymore.

Restarting computer does not solve the issue. So something is persisted when using the 32bit WebView2, which prevents the use later the 64bit WebView2 on that machine. The 32bit works fine however.

[zoli13]

Ok, I found the reason: the temp files (UserDataFolder).
WebView2 creates the folder 'EBWebView' inside it, and stores lots of files.
It seems the 32bit WebView2 can use the files created by the 64bit WebView2, but not other way around.

Workaround: use different UserDataFolder for 32/64 bit, or cleanup during App Startup. This later only works if 32 and 64bit won't run simultaneously, so different folder is recommended.

E.g.:

_browser.CreationProperties = new Microsoft.Web.WebView2.WinForms.CoreWebView2CreationProperties { 
	BrowserExecutableFolder = Path.Combine(OurApp.Instance.Path, "Microsoft.WebView2.FixedVersionRuntime"), 
	UserDataFolder = Path.Combine(Path.GetTempPath(), $"Microsoft.WebView2.FixedVersionRuntime.{(Environment.Is64BitProcess ? "64" : "32")}")
};

[LiangTheDev]

This should be the same issue as #2662. 32bit and 64bit app should use different user data folder for WebView2.