[LyX/master] Let Color::getX11HexName() output named colors correctly

[Koji Yokota]

commit b593bb0b91566d55841ac1e89b741743e513c5bb
Author: Koji Yokota <yokota at lyx.org>
Date:   Fri Jun 5 14:44:05 2026 +0900

    Let Color::getX11HexName() output named colors correctly
---
 src/Color.cpp | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/src/Color.cpp b/src/Color.cpp
index 5cca791389..7b7cc40c40 100644
--- a/src/Color.cpp
+++ b/src/Color.cpp
@@ -425,9 +425,16 @@ docstring const ColorSet::getGUIName(ColorCode c) const
 string const ColorSet::getX11HexName(ColorCode c, bool const darkmode) const
 {
 	InfoTab::const_iterator it = infotab.find(c);
-	if (it != infotab.end())
-		return darkmode ? "#" + it->second.darkhex32name.substr(3, 6) :
-		                  "#" + it->second.hex32name.substr(3, 6);
+	if (it != infotab.end()) {
+		if (darkmode)
+			return it->second.darkhex32name[0] == '#' ?
+			            "#" + it->second.darkhex32name.substr(3, 6) :
+			            it->second.darkhex32name;
+		else
+			return it->second.hex32name[0] == '#' ?
+			            "#" + it->second.hex32name.substr(3, 6) :
+			            it->second.hex32name;
+	}
 
 	lyxerr << "LyX internal error: Missing color"
 		  " entry in Color.cpp for " << c << '\n'
@@ -446,8 +453,7 @@ pair<string, string> const ColorSet::getAllX11HexNames(ColorCode c) const
 {
 	InfoTab::const_iterator it = infotab.find(c);
 	if (it != infotab.end())
-		return make_pair("#" + it->second.hex32name.substr(3, 6),
-		                 "#" + it->second.darkhex32name.substr(3, 6));
+		return make_pair(getX11HexName(c, false), getX11HexName(c, true));
 
 	lyxerr << "LyX internal error: Missing color"
 		  " entry in Color.cpp for " << c << '\n'