I hope it won’t keep you from making great music, since it may have been around since the introduction of the Notepad to Cubase as you can see by the following Forum thread from the days of Cubase 8.5 
p.s. As a programmer yourself, have you ever encountered bugs, that were known and documented, but just never made the top 100 list for any release? I have some background in software development myself, and I’ve definitely seen those kinds of things for every larger body of software I’ve ever worked on or product managed. I’ve got the funny feeling this bug is one of those. 