iD editor: how to choose which line to extend?

Take a situation where multiple ways are connected at a node. I would like to extend one of them (to keep tags, etc), but in the iD Editor, when I click the "Line" button, then the node, I cannot choose which way to extend.

(yes, I can just extend whichever way iD selects, then cut the way and merge the new section with the way I wanted to extend, but that's ugly and time consuming)

In Potlatch 2, I would select the way, then click the end node and extend the line. I'm thinking there must be a way to do this in iD that I've missed?