diff --git a/src/BranchList.h b/src/BranchList.h
index c7dd19603e..cdae7b6d0c 100644
--- a/src/BranchList.h
+++ b/src/BranchList.h
@@ -63,7 +63,7 @@ public:
 	///
 	std::string const & color() const;
 	/**
-	 * Set color from a string "#rrggbb".
+	 * Set color from a hexcolor string "#rrggbb" or a lyx color name.
 	 * Use Color:background if the string is no valid color.
 	 * This ensures compatibility with LyX 1.4.0 that had the symbolic
 	 * color "none" that was displayed as Color:background.
diff --git a/src/frontends/qt/GuiPainter.cpp b/src/frontends/qt/GuiPainter.cpp
index 4cb4699e6a..3b3b955662 100644
--- a/src/frontends/qt/GuiPainter.cpp
+++ b/src/frontends/qt/GuiPainter.cpp
@@ -242,12 +242,8 @@ void GuiPainter::image(int x, int y, int w, int h, graphics::Image const & i,
 	fillRectangle(x, y, w, h, Color_graphicsbg);
 
 	QImage image = qlimage.image();
-	
-	QPalette palette = QPalette();
-	QColor text_color = palette.color(QPalette::Active, QPalette::WindowText);
-	QColor bg_color = palette.color(QPalette::Active, QPalette::Window);
-	// guess whether we are in dark mode
-	if (revert_in_darkmode && text_color.black() < bg_color.black())
+
+	if (revert_in_darkmode && guiApp && guiApp->colorCache().isDarkMode())
 		// FIXME this is only a cheap approximation
 		// Ideally, replace colors as in GuiApplication::prepareForDarkmode()
 		image.invertPixels();