Unable to download workflow

Hello

I upgraded to 5.2.0.

I got this error message.

Unable to download workflow: The entity is not backed by an input stream, entity class is : java.io.InputStream

ı can see workflows at the example folder.When I click, I got this error message.

I also try to drag&drop from hub, I also get same error message.

I am not sure that I made correct preferances settings.

Can you help me to open example files?