diff -u -r .a/src/highlighting.c .b/src/highlighting.c
--- .a/src/highlighting.c	2017-11-19 12:45:42.000000001 +0300
+++ .b/src/highlighting.c	2018-02-16 00:30:50.683314483 +0300
@@ -646,7 +646,8 @@
 	SSM(sci, SCI_SETWRAPINDENTMODE, common_style_set.styling[GCS_LINE_WRAP_INDENT].background, 0);
 
 	/* Error indicator */
-	SSM(sci, SCI_INDICSETSTYLE, GEANY_INDICATOR_ERROR, INDIC_SQUIGGLEPIXMAP);
+	SSM(sci, SCI_INDICSETSTYLE, GEANY_INDICATOR_ERROR, INDIC_COMPOSITIONTHIN);
+	SSM(sci, SCI_INDICSETUNDER, GEANY_INDICATOR_ERROR, 1);
 	SSM(sci, SCI_INDICSETFORE, GEANY_INDICATOR_ERROR,
 		invert(common_style_set.styling[GCS_INDICATOR_ERROR].foreground));