bug#7342: 24.0.50; synchronised appearence of buffers in different frames

[Drew Adams]

> > It sounds like you are changing the text-scale factor, 
> > which affects the buffer, regardless of where it is displayed.
> 
> I am using the functions from the S-mouse-1 menu ("Change Default  
> Buffer Face"), increase or decrease buffer text size. I don't think  
> that a "text scaling" happens, by magnifying pixels or such.

Yes, they changed the behavior of S-mouse-1.  It now does so-called text scaling
or resizing.  The library for this behavior is face-remap.el.  See for example
`text-scale-increase' and `text-scale-adjust' (`C-x C-+'). For the doc, see the
Emacs manual, node `Temporary Face Changes'.

> > Alternatively, you can change the size of the default font for a  
> > frame, which affects all buffers displayed in that frame.
> 
> The functions in the menu do change the font used...

Those functions resize/scale the buffer text, as I said.  An _alternative_ is to
change the font of the `default' face for a given _frame_. You can do that in
various ways.  Again, see the SetFonts wiki page.