Yammer in SharePoint Classic Attachment missing

Hi All,

I recently explored the use of Yammer conversation in SharePoint Classic using the script editor and pasting javascript codes generated from Yammer (this is my reference).

Can I confirm that the embeded Yammer web part in SharePoint Classic doesn't support attachment?

Refer to the pics below:

This is the chat box in yammer:

This is the chat box in SharePoint yammer webpart:

The one in yammer has attachment button to it, but the same button can't be found in SP yammer webpart. 

Can anyone let me know if I missed something?

Cheers