I am using version 15.0.1 but this also happens in previous versions. We use multiple paragraph styles to format our text. We have noticed in some cases, not all when we copy the text frame the text box cuts off the last line when copied. Also when you click in a text box and begin to edit the last line disappears. We use many layers and many versions so we copy the text very often, this is causing problems with missing text.

To get our text formatted we use paragraph styles, we hit enter to go to the next style, this has always worked really well. Recently however, our style changed and they want the text to flow, not be on separate lines. We go back and delete the return to flow the text. I have also tried this same effect with nested paragraph styles, even with nested styles we get the same text box issue with the last line being cut off.

I recorded this happening in several instances and it can be viewed here: https://quad.box.com/s/4c1rwrbqpb5712250eo567t4ncv9mfzc