Yesterday, my code ran just fine under the previous Xcode version. Today, some print() statements seem to come with extra lines. I know it sounds stupid, but my code did not change in the meantime. It doesn't appear to come from anything I control, almost like some Apple code emits an extra line feed somewhere. It's just a Swift Mac App I built to make my digital art; otherwise, nothing else is incorrect, just these odd lines.
It's not as simple as just making a test case with a few print("***") statements, it seems to require other code to run in between calls to print. Most of my app is using CoreGraphics. It has no UI.
It's like when you see spurious Apple debugging info in the console sometimes, but it's only a blank line this time. It's not a big issue, just annoying.