diff --git a/notebooks/visualization/src/org/jetbrains/plugins/notebooks/visualization/NonIncrementalCellLines.kt b/notebooks/visualization/src/org/jetbrains/plugins/notebooks/visualization/NonIncrementalCellLines.kt
index d2e3c73b1757..b4f090e34f94 100644
--- a/notebooks/visualization/src/org/jetbrains/plugins/notebooks/visualization/NonIncrementalCellLines.kt
+++ b/notebooks/visualization/src/org/jetbrains/plugins/notebooks/visualization/NonIncrementalCellLines.kt
@@ -53,7 +53,9 @@ class NonIncrementalCellLines private constructor(private val document: Document
         }.count()
 
         val trimAtEnd = oldCells.asReversed().zip(newCells.asReversed()).takeWhile { (oldCell, newCell) ->
-          oldCell.type == newCell.type && oldCell.size == newCell.size &&
+          oldCell.type == newCell.type &&
+          oldCell.language == newCell.language &&
+          oldCell.size == newCell.size &&
           oldCell != oldAffectedCells.lastOrNull() && newCell != newAffectedCells.lastOrNull()
         }.count()
 
diff --git a/notebooks/visualization/src/org/jetbrains/plugins/notebooks/visualization/NotebookIntervalPointerImpl.kt b/notebooks/visualization/src/org/jetbrains/plugins/notebooks/visualization/NotebookIntervalPointerImpl.kt
index 03a43fb0c07f..71324dec2106 100644
--- a/notebooks/visualization/src/org/jetbrains/plugins/notebooks/visualization/NotebookIntervalPointerImpl.kt
+++ b/notebooks/visualization/src/org/jetbrains/plugins/notebooks/visualization/NotebookIntervalPointerImpl.kt
@@ -206,6 +206,13 @@ class NotebookIntervalPointerFactoryImpl(private val notebookCellLines: Notebook
   private fun makeSnapshot(interval: NotebookCellLines.Interval) =
     PointerSnapshot(pointers[interval.ordinal], interval)
 
+  private fun hasSingleIntervalsWithSameTypeAndLanguage(oldIntervals: List<NotebookCellLines.Interval>,
+                                                        newIntervals: List<NotebookCellLines.Interval>): Boolean {
+    val old = oldIntervals.singleOrNull() ?: return false
+    val new = newIntervals.singleOrNull() ?: return false
+    return old.type == new.type && old.language == new.language
+  }
+
   private fun updateChangedIntervals(e: NotebookCellLinesEvent, eventChanges: NotebookIntervalPointersEventChanges) {
     when {
       !e.isIntervalsChanged() -> {
@@ -214,7 +221,7 @@ class NotebookIntervalPointerFactoryImpl(private val notebookCellLines: Notebook
           eventChanges.add(OnEdited(pointers[editedInterval.ordinal], editedInterval, editedInterval))
         }
       }
-      e.oldIntervals.size == 1 && e.newIntervals.size == 1 && e.oldIntervals.first().type == e.newIntervals.first().type -> {
+      hasSingleIntervalsWithSameTypeAndLanguage(e.oldIntervals, e.newIntervals) -> {
         // only one interval changed size
         for (editedInterval in e.newAffectedIntervals) {
           val ptr = pointers[editedInterval.ordinal]