This is not a workaround for the functionality that was removed @JoanaC and its beyond exasperating that you would post something so inane and useless as a "workaround".  You clearly have no comprehension of what we have all been saying re: the needed functionality that was ended without any notice or communication.

I'm well aware of how to add an attachment to an invoice.  My IQ exceeds that of the average gnat.  I'm trying to add a REBILLABLE item (that already has an attachment) to a client invoice.  Do you get "points" for posting completely irrelevant How-To steps?

Using your "workaround" would create the need to manually download from QBO, and then manually attach over 1000 documents to client invoices every month.  Until a couple of weeks ago - there was no addtl work required. 

This is NOT a workaround.  Its absurd that you would suggest it as such.

I'm embarrassed for you.