diff --git a/fleet/andel/srcCommonMain/andel/editor/MutableEditor.kt b/fleet/andel/srcCommonMain/andel/editor/MutableEditor.kt
index f21af0d678e2..dcc4dec7db74 100644
--- a/fleet/andel/srcCommonMain/andel/editor/MutableEditor.kt
+++ b/fleet/andel/srcCommonMain/andel/editor/MutableEditor.kt
@@ -151,7 +151,7 @@ interface EditorLayout {
 interface MutableEditorLayout : EditorLayout {
   fun unfold(affectedFolds: List<Interval<*, Fold>>)
 
-  fun toggleFolds(add: List<Interval<*, Fold>>, remove: List<Interval<*, Fold>>, isConfirm: Boolean = false)
+  fun toggleFolds(add: List<Interval<*, Fold>>, remove: List<Interval<*, Fold>>)
 }
 
 // Order is significant: the greater index, the more specific is the command type
diff --git a/fleet/andel/srcCommonMain/andel/editor/SimpleEditor.kt b/fleet/andel/srcCommonMain/andel/editor/SimpleEditor.kt
index 7ce50dc12122..2704bf075e38 100644
--- a/fleet/andel/srcCommonMain/andel/editor/SimpleEditor.kt
+++ b/fleet/andel/srcCommonMain/andel/editor/SimpleEditor.kt
@@ -119,9 +119,14 @@ data class SimpleEditorLayout(
     )
   }
 
-  override fun unfold(affectedFolds: List<Interval<*, Fold>>) {}
+  override fun unfold(affectedFolds: List<Interval<*, Fold>>) {
+    toggleFolds(emptyList(), affectedFolds)
+  }
 
-  override fun toggleFolds(add: List<Interval<*, Fold>>, remove: List<Interval<*, Fold>>, isConfirm: Boolean) {}
+  override fun toggleFolds(add: List<Interval<*, Fold>>, remove: List<Interval<*, Fold>>) {
+    folds = folds.removeByIds(remove.map { it.id as Long }).addIntervals(add as List<Interval<Long, Fold>>)
+  // we should update lines cache here, but right now simple editor with folds is used only in tests
+  }
 }
 
 class SimpleEditorLayoutComponent(var state: SimpleEditorLayout) : DocumentComponent {