Replaced GTK3 palette font styling with CSS-compliant properties derived from PangoFontDescription, avoiding the deprecated Pango font: syntax in generated CSS.

Added a GTK3-only helper to translate Pango font fields into font-family, font-size, font-style, font-weight, font-variant, and font-stretch CSS declarations while preserving GTK2 behavior under #if !HAVE_GTK3.
Reused the GTK3 font CSS helper in the main UI font styling path to eliminate remaining Pango font: shorthand usage that triggers GTK3 theme parsing warnings.
Exposed the GTK3 font CSS helper in gtkutil so callers can emit CSS-compliant font properties consistently.

src/fe-gtk/gtkutil.c

@@ -161,6 +161,118 @@ gtkutil_button_new_from_stock (const char *stock, const char *label)
 }
 
 #if HAVE_GTK3
+void
+gtkutil_append_font_css (GString *css, const PangoFontDescription *font_desc)
+{
+	PangoFontMask mask;
+
+	if (!font_desc)
+		return;
+
+	mask = pango_font_description_get_set_fields (font_desc);
+
+	if (mask & PANGO_FONT_MASK_FAMILY)
+	{
+		const char *family = pango_font_description_get_family (font_desc);
+
+		if (family && *family)
+			g_string_append_printf (css, " font-family: \"%s\";", family);
+	}
+
+	if (mask & PANGO_FONT_MASK_STYLE)
+	{
+		const char *style = "normal";
+
+		switch (pango_font_description_get_style (font_desc))
+		{
+		case PANGO_STYLE_ITALIC:
+			style = "italic";
+			break;
+		case PANGO_STYLE_OBLIQUE:
+			style = "oblique";
+			break;
+		default:
+			style = "normal";
+			break;
+		}
+
+		g_string_append_printf (css, " font-style: %s;", style);
+	}
+
+	if (mask & PANGO_FONT_MASK_VARIANT)
+	{
+		const char *variant = "normal";
+
+		if (pango_font_description_get_variant (font_desc) == PANGO_VARIANT_SMALL_CAPS)
+			variant = "small-caps";
+
+		g_string_append_printf (css, " font-variant: %s;", variant);
+	}
+
+	if (mask & PANGO_FONT_MASK_WEIGHT)
+	{
+		int weight = (int) pango_font_description_get_weight (font_desc);
+
+		if (weight < 100)
+			weight = 100;
+		if (weight > 900)
+			weight = 900;
+
+		g_string_append_printf (css, " font-weight: %d;", weight);
+	}
+
+	if (mask & PANGO_FONT_MASK_STRETCH)
+	{
+		const char *stretch = "normal";
+
+		switch (pango_font_description_get_stretch (font_desc))
+		{
+		case PANGO_STRETCH_ULTRA_CONDENSED:
+			stretch = "ultra-condensed";
+			break;
+		case PANGO_STRETCH_EXTRA_CONDENSED:
+			stretch = "extra-condensed";
+			break;
+		case PANGO_STRETCH_CONDENSED:
+			stretch = "condensed";
+			break;
+		case PANGO_STRETCH_SEMI_CONDENSED:
+			stretch = "semi-condensed";
+			break;
+		case PANGO_STRETCH_SEMI_EXPANDED:
+			stretch = "semi-expanded";
+			break;
+		case PANGO_STRETCH_EXPANDED:
+			stretch = "expanded";
+			break;
+		case PANGO_STRETCH_EXTRA_EXPANDED:
+			stretch = "extra-expanded";
+			break;
+		case PANGO_STRETCH_ULTRA_EXPANDED:
+			stretch = "ultra-expanded";
+			break;
+		default:
+			stretch = "normal";
+			break;
+		}
+
+		g_string_append_printf (css, " font-stretch: %s;", stretch);
+	}
+
+	if (mask & PANGO_FONT_MASK_SIZE)
+	{
+		double size = (double) pango_font_description_get_size (font_desc) / PANGO_SCALE;
+		char size_buf[G_ASCII_DTOSTR_BUF_SIZE];
+		const char *unit = "pt";
+
+		if (pango_font_description_get_size_is_absolute (font_desc))
+			unit = "px";
+
+		g_ascii_formatd (size_buf, sizeof (size_buf), "%.2f", size);
+		g_string_append_printf (css, " font-size: %s%s;", size_buf, unit);
+	}
+}
+
 void
 gtkutil_apply_palette (GtkWidget *widget, const GdkRGBA *bg, const GdkRGBA *fg,
                        const PangoFontDescription *font_desc)
@@ -183,7 +295,6 @@ gtkutil_apply_palette (GtkWidget *widget, const GdkColor *bg, const GdkColor *fg
 		GString *css;
 		gchar *bg_color = NULL;
 		gchar *fg_color = NULL;
-		gchar *font_str = NULL;
 
 		if (!bg && !fg && !font_desc)
 		{
@@ -217,11 +328,7 @@ gtkutil_apply_palette (GtkWidget *widget, const GdkColor *bg, const GdkColor *fg
 			fg_color = gdk_rgba_to_string (fg);
 			g_string_append_printf (css, " color: %s;", fg_color);
 		}
-		if (font_desc)
+		gtkutil_append_font_css (css, font_desc);
-		{
-			font_str = pango_font_description_to_string (font_desc);
-			g_string_append_printf (css, " font: %s;", font_str);
-		}
 		g_string_append (css, " }");
 
 		gtk_css_provider_load_from_data (provider, css->str, -1, NULL);
@@ -235,7 +342,6 @@ gtkutil_apply_palette (GtkWidget *widget, const GdkColor *bg, const GdkColor *fg
 		g_string_free (css, TRUE);
 		g_free (bg_color);
 		g_free (fg_color);
-		g_free (font_str);
 	}
 #else
 	gtk_widget_modify_base (widget, GTK_STATE_NORMAL, bg);

src/fe-gtk/gtkutil.h

@@ -53,6 +53,7 @@ gboolean gtkutil_tray_icon_supported (GtkWindow *window);
 #if HAVE_GTK3
 void gtkutil_apply_palette (GtkWidget *widget, const GdkRGBA *bg, const GdkRGBA *fg,
                             const PangoFontDescription *font_desc);
+void gtkutil_append_font_css (GString *css, const PangoFontDescription *font_desc);
 #else
 void gtkutil_apply_palette (GtkWidget *widget, const GdkColor *bg, const GdkColor *fg,
                             const PangoFontDescription *font_desc);

src/fe-gtk/maingui.c

@@ -124,7 +124,6 @@ mg_apply_font_css (GtkWidget *widget, const PangoFontDescription *desc,
 {
 	GtkStyleContext *context;
 	GtkCssProvider *provider;
-	char *font_str;
 	GString *css;
 
 	if (!widget || !desc)
@@ -141,13 +140,13 @@ mg_apply_font_css (GtkWidget *widget, const PangoFontDescription *desc,
 		g_object_set_data_full (G_OBJECT (widget), provider_key, provider, g_object_unref);
 	}
 
-	font_str = pango_font_description_to_string (desc);
 	css = g_string_new (".");
 	g_string_append (css, class_name);
-	g_string_append_printf (css, " { font: %s; }", font_str);
+	g_string_append (css, " {");
+	gtkutil_append_font_css (css, desc);
+	g_string_append (css, " }");
 	gtk_css_provider_load_from_data (provider, css->str, -1, NULL);
 	g_string_free (css, TRUE);
-	g_free (font_str);
 
 	gtk_style_context_add_class (context, class_name);
 	gtk_style_context_add_provider (context, GTK_STYLE_PROVIDER (provider),

src/fe-gtk/xtext.c

@@ -293,7 +293,7 @@ xtext_surface_from_window (GdkWindow *window)
 	int height;
 	cairo_t *cr;
 
-	if (!window)
+	if (!window || !GDK_IS_WINDOW (window))
 		return NULL;
 
 	width = gdk_window_get_width (window);
@@ -925,14 +925,39 @@ gtk_xtext_get_pointer (GdkWindow *window, gint *x, gint *y, GdkModifierType *mas
 #if !HAVE_GTK3
 	gdk_window_get_pointer (window, x, y, mask);
 #else
-	GdkDisplay *display = gdk_window_get_display (window);
+	GdkDisplay *display;
-	GdkSeat *seat = gdk_display_get_default_seat (display);
+	GdkSeat *seat;
-	GdkDevice *device = gdk_seat_get_pointer (seat);
+	GdkDevice *device;
 	gint root_x = 0;
 	gint root_y = 0;
 	gint win_x = 0;
 	gint win_y = 0;
 
+	if (!window || !GDK_IS_WINDOW (window))
+	{
+		if (x)
+			*x = 0;
+		if (y)
+			*y = 0;
+		if (mask)
+			*mask = 0;
+		return;
+	}
+
+	display = gdk_window_get_display (window);
+	if (!display)
+	{
+		if (x)
+			*x = 0;
+		if (y)
+			*y = 0;
+		if (mask)
+			*mask = 0;
+		return;
+	}
+
+	seat = gdk_display_get_default_seat (display);
+	device = gdk_seat_get_pointer (seat);
 	if (!device)
 	{
 		if (x)
@@ -1049,8 +1074,16 @@ gtk_xtext_realize (GtkWidget * widget)
 		xtext->ts_x = xtext->ts_y = 0;
 	}
 
-	xtext->hand_cursor = gdk_cursor_new_for_display (gdk_window_get_display (window), GDK_HAND1);
+	if (window && GDK_IS_WINDOW (window))
-	xtext->resize_cursor = gdk_cursor_new_for_display (gdk_window_get_display (window), GDK_LEFT_SIDE);
+	{
+		GdkDisplay *display = gdk_window_get_display (window);
+
+		if (display)
+		{
+			xtext->hand_cursor = gdk_cursor_new_for_display (display, GDK_HAND1);
+			xtext->resize_cursor = gdk_cursor_new_for_display (display, GDK_LEFT_SIDE);
+		}
+	}
 
 	gtk_xtext_clear_background (widget);
 
@@ -2712,9 +2745,11 @@ gtk_xtext_selection_get (GtkWidget * widget,
 #if HAVE_GTK3
 			GdkWindow *window = gtk_widget_get_window (widget);
 
-			if (!window)
+			if (!window || !GDK_IS_WINDOW (window))
 				break;
 			display = gdk_window_get_display (window);
+			if (!display)
+				break;
 #endif
 #if !HAVE_GTK3
 			display = gdk_window_get_display (widget->window);