When we assign out the individual tasks, we have found that when a Technician selects an open task from the "My Tasks" section of his home tab, that all of the options for that task appear except for the button to enable the assignee to add an additional attachment during the completion of that task. 

See below:

The assigned technician can add an attachment by going to Quick Action, then My Tasks and opening the task from there. 

This feels almost like the attachment button is missing by mistake on the Home tab as it would be incredibly useful to complete tasks quickly, and be able to add justification attachments right from this screen. I'm not sure if this is technically a bug, or a feature request? Maybe both? 

Thanks,

Jeff