Re: buffer-face-set changes the fringe, is it a bug?

[Gregory Heytings via "Emacs development discussions." <emacs-devel@gnu.org>]

>
>> In fact the manual is not as clear as you think, it states (see https://www.gnu.org/software/emacs/manual/html_node/elisp/Fringe-Bitmaps.html ):
>>
>> (fringe bitmap [face])
>>
>> The optional face names a face whose foreground color is used to 
>> display the bitmap; this face is automatically merged with the fringe 
>> face.
>>
>> For me this means that the fringe face is used to display the bitmaps 
>> in the fringe, except the :foreground property which can optionally be 
>> imported from another face.
>
> Thanks, I clarified the meaning of FACE in that case.
>

Okay, the meaning is clear now.  But, IMO, it would be better to change 
this behavior as follows:

"The optional @var{face} names a face whose foreground and background 
colors are to be used to display the bitmap; this face is automatically 
merged with the @code{fringe} face.  If @var{face} is omitted, that means 
to use the *@code{fringe}* face."

I at least would expect that the default behavior when displaying 
something in the fringe would be to use the fringe face.  It is then still 
possible to use the 'default' face if one wishes to do so (but why would 
one wish to do this?).  Apparently this change is possible without 
modifying any of the files in the "lisp" directory.

Gregory