bug#23946: 25.0.91; Unicode issue on OS X (Emacs 25)

[Toon Claes <toon@iotcl.com>]

"Артур Файзрахманов" <heraldhoi@gmail.com> writes:

> Hi!  I'm using Emacs pretest version 25.0.91.1 on OS X El Capital.  If I
> launch Emacs from GUI (e.g. from Applications folder or using Spotlight)
> Unicode characters in mode-line are rendered wrong (I use diminish mode
> to substitute some minor mode names with Unicode characters).  This is
> not a case if I start Emacs manually from shell.

Which Unicode symbols are you referring to?
In particular, are you talking about multi-color symbols (Emoji) or
other Unicode symbols?

Because, support for multi-color fonts was deliberately disabled in
commit 9344612d3cd164317170b6189ec43175757e4231.

So the SNOWMAN (U+2603) symbol will be displayed in black/white, but not
in color. ☃

This was also mentioned in NEWS:

> ** On the OS X Cocoa ("Nextstep") port, multicolor font (such as color
> emoji) display is disabled.  This feature was accidentally added when
> Emacs 24.4 included the new Core Text based font backend code that was
> originally implemented for a non-mainline port.  This will be enabled
> again once it is also implemented in Emacs on free operating systems.
> If some symbols, such as emoji, do not display, we suggest to install
> an appropriate font, such as Symbola; then they will be displayed,
> albeit without the color effects.