diff --git a/src/lang/english_US.txt b/src/lang/english_US.txt
--- a/src/lang/english_US.txt
+++ b/src/lang/english_US.txt
@@ -2617,6 +2617,8 @@ STR_LINKGRAPH_LEGEND_UNUSED             
 STR_LINKGRAPH_LEGEND_SATURATED                                  :{TINY_FONT}{BLACK}saturated
 STR_LINKGRAPH_LEGEND_OVERLOADED                                 :{TINY_FONT}{BLACK}overloaded
 
+# Linkgraph tooltip
+
 # Base for station construction window(s)
 STR_STATION_BUILD_COVERAGE_AREA_TITLE                           :{BLACK}Coverage area highlight
 STR_STATION_BUILD_COVERAGE_OFF                                  :{BLACK}Off