diff --git a/src/gen-arabic-joining-list.py b/src/gen-arabic-joining-list.py
index 78c44c35d..8162a4a3e 100755
--- a/src/gen-arabic-joining-list.py
+++ b/src/gen-arabic-joining-list.py
@@ -54,6 +54,8 @@ def read_joining_uu (f):
 		fields = [x.strip () for x in line.split (';')]
 		if len (fields) == 1:
 			continue
+		if fields[2] in {'T', 'U'}:
+			continue
 
 		values.add (int (fields[0], 16))
 
diff --git a/src/hb-ot-shape-complex-arabic-joining-list.hh b/src/hb-ot-shape-complex-arabic-joining-list.hh
index 140310333..c022d4bb0 100644
--- a/src/hb-ot-shape-complex-arabic-joining-list.hh
+++ b/src/hb-ot-shape-complex-arabic-joining-list.hh
@@ -25,7 +25,6 @@ has_arabic_joining (hb_script_t script)
     case HB_SCRIPT_ARABIC:
     case HB_SCRIPT_CHORASMIAN:
     case HB_SCRIPT_HANIFI_ROHINGYA:
-    case HB_SCRIPT_KAITHI:
     case HB_SCRIPT_MANDAIC:
     case HB_SCRIPT_MANICHAEAN:
     case HB_SCRIPT_MONGOLIAN:
diff --git a/src/hb-ot-shape-complex-use.cc b/src/hb-ot-shape-complex-use.cc
index 981df2d59..a1e25bdd8 100644
--- a/src/hb-ot-shape-complex-use.cc
+++ b/src/hb-ot-shape-complex-use.cc
@@ -36,7 +36,7 @@
 #include "hb-ot-shape-complex-vowel-constraints.hh"
 
 /* buffer var allocations */
-#define use_category() complex_var_u8_0()
+#define use_category() complex_var_u8_1()
 
 
 /*
diff --git a/test/shaping/data/in-house/tests/use.tests b/test/shaping/data/in-house/tests/use.tests
index 7631c3b3c..6328d3c5f 100644
--- a/test/shaping/data/in-house/tests/use.tests
+++ b/test/shaping/data/in-house/tests/use.tests
@@ -12,3 +12,4 @@
 ../fonts/4afb0e8b9a86bb9bd73a1247de4e33fbe3c1fd93.ttf::U+1C00,U+1C27,U+1C28,U+1C34,U+1C35:[uni1C35=0+500|uni1C34=0+500|uni1C28=0+500|uni1C27=0+500|uni1C00=0+500]
 ../fonts/4afb0e8b9a86bb9bd73a1247de4e33fbe3c1fd93.ttf::U+0D4E,U+0D15,U+0D4D,U+0D15,U+0D46:[uni0D15=0+500|uni0D4E=0+500|uni0D4D=0+500|uni0D46=3+500|uni0D15=3+500]
 ../fonts/4afb0e8b9a86bb9bd73a1247de4e33fbe3c1fd93.ttf::U+1102D,U+11046,U+11013,U+11046,U+11013,U+11046:[u11013=0+500|u11046_u11013=0+500|u1102D_u11046=0+500|u11046=0+500]
+../fonts/4afb0e8b9a86bb9bd73a1247de4e33fbe3c1fd93.ttf::U+11083:[.notdef=0+500]