diff --git a/mono_envsetup.sh b/mono_envsetup.sh
index cf90bdf72..83c628a39 100644
--- a/mono_envsetup.sh
+++ b/mono_envsetup.sh
@@ -90,7 +90,7 @@ MONO_ENV_OPTIONS_ADD "--server"
 if [ -n "$MONO_FACADES" ]; then
 	echo "INFO: Mono facades path was already set to: $MONO_FACADES"
 else
-	for USR in "/usr" "/Library/Frameworks/Mono.framework/Versions/${CURRENT_MONO_VERSION}"; do
+	for USR in "/opt/mono" "/usr" "/Library/Frameworks/Mono.framework/Versions/${CURRENT_MONO_VERSION}"; do
 		for API in "${MINIMUM_NET_FRAMEWORK}-api" "4.5"; do # 4.5 is fallback path that existed before Mono decided to split Facades on per-API basis - still available
 			if [ -d "${USR}/lib/mono/${API}/Facades" ]; then
 				export MONO_FACADES="${USR}/lib/mono/${API}/Facades"