diff --git a/FAQ b/FAQ index 921c493..ecf7af8 100644 --- a/FAQ +++ b/FAQ @@ -165,3 +165,30 @@ Apply [1]. [1] http://st.suckless.org/patches/delkey +## BadLength X error in Xft when trying to render emoji + +Xft makes st crash when rendering color emojis with the following error: + +"X Error of failed request: BadLength (poly request too large or internal Xlib length error)" + Major opcode of failed request: 139 (RENDER) + Minor opcode of failed request: 20 (RenderAddGlyphs) + Serial number of failed request: 1595 + Current serial number in output stream: 1818" + +This is a known bug in Xft (not st) which happens on some platforms and +combination of particular fonts and fontconfig settings. + +See also: +https://gitlab.freedesktop.org/xorg/lib/libxft/issues/6 +https://bugs.freedesktop.org/show_bug.cgi?id=107534 +https://bugzilla.redhat.com/show_bug.cgi?id=1498269 + +The solution is to remove color emoji fonts or disable this in the fontconfig +XML configuration. As an ugly workaround (which may work only on newer +fontconfig versions (FC_COLOR)), the following code can be used to mask color +fonts: + + FcPatternAddBool(fcpattern, FC_COLOR, FcFalse); + +Please don't bother reporting this bug to st, but notify the upstream Xft +developers about fixing this bug.