diff --git a/app/scripts/10.0_release_build_and_deploy b/app/scripts/10.0_release_build_and_deploy
index f16b4212ec..4b6db4d94c 100755
--- a/app/scripts/10.0_release_build_and_deploy
+++ b/app/scripts/10.0_release_build_and_deploy
@@ -12,6 +12,7 @@ BUILD_ONLY=0
 if [ "`uname`" = "Darwin" ]; then
 	export SAFARI_APPEX="$ROOT_DIR/../safari-web-extension-builds/ZoteroSafariExtension.appex"
 	export SAFARI_EXT_RESOURCES="$ROOT_DIR/../safari-web-extension-builds/release/safari"
+	export SAFARI_APP_EXTENSION="$ROOT_DIR/../safari-app-extension-builds/release/ZoteroSafariExtension.appex"
 	if [ ! -d "$SAFARI_APPEX" ]; then
 		echo "Safari extension stub not found at $SAFARI_APPEX -- aborting" >&2
 		exit 1
@@ -20,6 +21,10 @@ if [ "`uname`" = "Darwin" ]; then
 		echo "Safari web extension not found in $SAFARI_EXT_RESOURCES -- aborting" >&2
 		exit 1
 	fi
+	if [ ! -d "$SAFARI_APP_EXTENSION" ]; then
+		echo "Safari App Extension not found at $SAFARI_APP_EXTENSION -- aborting" >&2
+		exit 1
+	fi
 fi
 
 while getopts "b" opt; do