diff --git a/mail/build.mk b/mail/build.mk
index f50b28fc2a..caf1b6acbf 100644
--- a/mail/build.mk
+++ b/mail/build.mk
@@ -43,6 +43,8 @@ endif
 
 TIERS += app
 
+tier_app_dirs += xpfe/components/autocomplete
+
 ifdef MOZ_EXTENSIONS
 tier_app_dirs += extensions
 endif
diff --git a/suite/build.mk b/suite/build.mk
index 575c92b0c0..9370d09307 100644
--- a/suite/build.mk
+++ b/suite/build.mk
@@ -43,6 +43,8 @@ endif
 
 TIERS += app
 
+tier_app_dirs += xpfe/components/autocomplete
+
 ifdef MOZ_EXTENSIONS
 tier_app_dirs += extensions
 endif