When a font style is applied to the newline character, certain styles - such as background colors - normally are extended to the end of the visual line. Suddenly this has changed for me, and the fonts make it look like the newline character is a trailing space.
What can cause this?
I am running Emacs 27.2 on Open Suse 15.1 64 bit. I recently performed a major update of packages, after the updater had been stuck for a while, so I suspect something in there might be causing the change.