Block views with no results are not displayed.
However if a block view display has a no results behaviour configured this should be honoured.
For example - I have a block view "Current manager"
If manager is assigned to user it says "Your current manager is xxx"
If no manager is assigned the no results behaviour is to show a texfield saying "You do not currently have a manager assigned"
Homebox currently does not output any block in the second situation.
Closed: won't fix
Code
Please create a new Drupal 8+ (3.0.x) issue, referencing this one, if this is
still relevant for Drupal 8+ (3.0.x).
As this issue was created for Drupal 7 which is close to EOL and won't
receive any new features here anymore (unless someone implements them or
sponsors development) I'm closing this issue for cleanup now.
If anyone works on this or has a solution, feel free to reopen! 😄
Thank you.