I rarely find myself asking questions since about everything has already been answered somewhere; not this one though.
I use Emacs 25.3.2 with AucTeX 12.1.1 on Ubuntu 16.04 and for a while now, whenever I enable TeX-Folding (invoking
TeX-fold-buffer), the display string for folded elements (citations, refs and, footnotes) are followed by visual newlines (see screenshot link).
This also affects my custom display strings, which do not contain newline chars;
the problem is therefore not due to the string containing new line chars, but to some quirk in how folding is applied.
I have no clues how to investigate this any further… any ideas?
Many thanks and all the best!
screenshot here: http://www.phylax-computerkunst.de/download/auctex_folding_error.png