Clarification about Logo vs Thumbnail behavior in Dataverse 6.4

[Tutasi]

Hello, We are working with Dataverse version 6.4 and we have some doubts about how Logo and Thumbnail images are supposed to work for subdataverses.

In a main Dataverse, when we add subdataverses to Featured Dataverses, we notice that only the Logo appears, even if a Thumbnail is configured.

Is it expected that only the Logo is shown everywhere, and that Thumbnail is not used? Or are we missing some configuration? 

Thanks in advance for your help