Multiple Number Dialing in Teams for Skype for Business Users

Hello together, 

do you also encounter the problem when you search for a user in Microsoft Teams and click on the contact in the result, that the "Multiple Number Dialing" button is not displayed in the general chat windows for that user? The button is not visible, when the selected user is a Skype for Business user. For Teams user this is working fine. 

Here is an example fo a selected Skype for Business user: 

This is how it looks like for a Teams user 

As you can see, the arrow is missing for the Skype for Business user. This makes it more complex to call additional numbers for this account, because we have to search for it in Outlook.

The funny thing - as soon as you open a pop-out chat for the Skype for Business user, the button is visible and can be used.

Do you know, if this is by design or do you encounter the same "problem"?

Thank you very much for your response. 

Greets,
Markus