emacs-27 97747e6: Tell people how to remove fontconfig customizations

[Robert Pluim]

branch: emacs-27
commit 97747e6fb9890ef528cbe21636cc99508efeba2b
Author: Robert Pluim <rpluim@gmail.com>
Commit: Robert Pluim <rpluim@gmail.com>

    Tell people how to remove fontconfig customizations
---
 etc/PROBLEMS | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/etc/PROBLEMS b/etc/PROBLEMS
index 7499726..cfca598 100644
--- a/etc/PROBLEMS
+++ b/etc/PROBLEMS
@@ -693,6 +693,11 @@ versions of gnutls-cli, or use Emacs's built-in gnutls 
support.
 
 ** Characters are displayed as empty boxes or with wrong font under X.
 
+*** This may be due to your local fontconfig customization.
+Try removing or moving aside "$XDG_CONFIG_HOME/fontconfig/conf.d" and
+"$XDG_CONFIG_HOME/fontconfig/fonts.conf"
+($XDG_CONFIG_HOME is treated as "~/.config" if not set)
+
 *** This can occur when two different versions of FontConfig are used.
 For example, XFree86 4.3.0 has one version and Gnome usually comes
 with a newer version.  Emacs compiled with Gtk+ will then use the