Hello,
Thank you for posting in Microsoft Q&A.
Based on the description, I understand your question is related to Microsoft Kiosk Browser.
Compare the network requests and responses between Edge and Kiosk Browser. Look for any differences that might indicate why the app isn't loading in Kiosk Browser. Check your app is compatible with the version of Kiosk Browser you're using. There might be specific features or APIs that Kiosk Browser doesn't support. Check the official documentation or support forums for Kiosk Browser. There might be known issues or specific settings that need to be configured for your app to work correctly.
Here is also a reference link:
https://learn.microsoft.com/en-us/windows/msix/packaging-tool/tool-known-issues
Have a nice day.
Best Regards,
Molly
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