Fix anti-aliasing

sway/tree/container.c

@@ -582,6 +582,10 @@ static void update_title_texture(struct sway_container *con,
 	cairo_surface_t *surface = cairo_image_surface_create(
 			CAIRO_FORMAT_ARGB32, width, height);
 	cairo_t *cairo = cairo_create(surface);
+	cairo_set_source_rgba(cairo, class->background[0], class->background[1],
+			class->background[2], class->background[3]);
+	cairo_paint(cairo);
+	cairo_set_antialias(cairo, CAIRO_ANTIALIAS_BEST);
 	PangoContext *pango = pango_cairo_create_context(cairo);
 	cairo_set_source_u32(cairo, class->text);
 	cairo_move_to(cairo, 0, 0);