Eli Zaretskii <eliz@gnu.org> writes:

[...]

>> > In general, if the default face's font supports some character, Emacs
>> > will use that font, so I don't quite understand why you need to
>> > customize your fonts just to have characters displayed by the default
>> > face's font.  It shouldn't be needed, if the font really supports
>> > those characters
>> 
>> Except that it /is/ needed, as I've described in my original question?
>
> I'd need to see full recipe starting from "emacs -Q" to understand
> what exactly is needed and why.

Please evaluate:

(let ((buf (get-buffer-create "test encodings")))
  (with-current-buffer buf
    (erase-buffer)
    (insert "Encoding windows-1251: "
            (propertize "привет\n" 'charset 'windows-1251))
    (insert "Encoding      unicode: "
            (propertize "привет\n" 'charset 'unicode)))
  (switch-to-buffer-other-window buf))

What I see in "emacs -Q" is attached as Emacs window snapshot. Please
notice how two strings look very different where encodings differ. What
I see in my "regular" Emacs is almost the same, just in larger font
size.

The question is why Emacs doesn't use the default font for windows-1251
encoding when the font definitely has all the needed glyphs?

Thanks,
-- Sergey