bug#50795: C-u C-x = improvements

[Stefan Kangas]

積丹尼 Dan Jacobson <jidanni@jidanni.org> writes:

>               display: by this font (glyph code)
>                                                 ^ I would add a colon (:) 
> here,
>                                                 Else the next line seems to
>                                                 have a header field "x":
>     x:-sony-fixed-medium-r-normal--16-120-100-100-c-80-iso8859-1 (#x46)
>                                                 Or maybe it does.

Perhaps a colon would be useful here.  I thought about some other way of
making this more clear, but couldn't think of anything better.