bug#19873: Ill-formed regular expression is constructed in forward-paragraph.

[Eli Zaretskii]

> From: Marcin Borkowski <mbork@amu.edu.pl>
> Date: Sun, 26 Feb 2017 17:44:51 +0100
> Cc: 19873@debbugs.gnu.org
> 
> First of all, my Emacs has this as paragraph-start:
> 
> "\\|[        ]*$"
> 
> and this as paragraph-separate:
> 
> "[    ]*$"
> 
> and frankly speaking, I'm not sure why they differ at all (by default).

I believe this is explained in the Emacs manual, node "Paragraphs".
In a nutshell, these two regexps have different purposes.