diff --git a/solutions/jetbrains.mps.unification.tree/imports/mps-unification b/solutions/jetbrains.mps.unification.tree/imports/mps-unification
index bc3f2a77..77a6b805 160000
--- a/solutions/jetbrains.mps.unification.tree/imports/mps-unification
+++ b/solutions/jetbrains.mps.unification.tree/imports/mps-unification
@@ -1 +1 @@
-Subproject commit bc3f2a77242575e85e4c3ca036d77c1bb3742603
+Subproject commit 77a6b805bf4577a437627ad3164ce15c96279fee