On May 27, 2009, at 10:12 PM, Kenichi Handa wrote:
> If the arg FRAME is nil, set-face-attribute changes
> attributes on all frames plus the default for new frames
>
> But customize-face changes only the attributes of existing
> frames.

> (customize-face 'default) ;; set :background back to "#ffffff"
>
> (face-attribute 'default :background nil) => "#ffffff"
> (face-attribute 'default :background t) => "gray"

So is this a new, intentional "feature"?

I presume there has been a discussion about this... because without  
knowing the reasoning behind this, I'd say it was a bad call.  Very  
confusing to users, who, by default, shouldn't be concerned with frame- 
specific faces.  Note that even "save for future sessions" won't set  
the face for future frames.  How would I set a face through the  
customize interface that is valid for current and future frames?