@John-Sampson said in regex and newlines:
However, Notepad++ included newlines so that it changed each line to “ren \1” on one line, “\1” on a new line
So if you were using \1 that assumes you were searching in regular expression mode. Then I’m going to assume your find what field also captured the CR and LF characters which are EOL markers. Returning those would likely produce the result you saw.
I think you need to post the Find What field you used so we can confirm what you were doing.
Oh, just saw that @peterjones also believes the same.
Terry