Incorporate Modern Authentication

[IfEyeOnlyKnew]

We are using the Picture Profile Uploader application, https://github.com/SharePoint/PnP/tree/master/Samples/Core.ProfilePictureUploader. In SharePoint Online you can Allow or Block third party apps when apply "Apps that don't use modern authentication".

When we have the setting at "block" this application will not run correct. Obviously the authentication is the issue. Is there a way to change in the code to use this type of method?

Not a C# developer.