I can't find the bug tracker anymore, but we just upgraded to 4.6 and now the buttons are missing in the app marketplace. Example below of a free theme.

 

Edit to clarify: The button to purchase or upgrade the app is missing from the small, empty rectangular box above "Resource Information"

Edited July 21, 20213 yr by ahc

Submit a ticket and we'll take a look. I haven't seen this happen before.