diff --git a/platform/platform-impl/src/com/intellij/openapi/editor/impl/CaretModelImpl.java b/platform/platform-impl/src/com/intellij/openapi/editor/impl/CaretModelImpl.java
index 527125019b49..6221b8867153 100644
--- a/platform/platform-impl/src/com/intellij/openapi/editor/impl/CaretModelImpl.java
+++ b/platform/platform-impl/src/com/intellij/openapi/editor/impl/CaretModelImpl.java
@@ -264,7 +264,7 @@ public class CaretModelImpl implements CaretModel, PrioritizedDocumentListener,
   @Nullable
   @Override
   public Caret addCaret(@NotNull VisualPosition pos) {
-    myEditor.assertIsDispatchThread();
+    EditorImpl.assertIsDispatchThread();
     CaretImpl caret = new CaretImpl(myEditor);
     caret.moveToVisualPosition(pos, false);
     if (addCaret(caret)) {
@@ -291,7 +291,7 @@ public class CaretModelImpl implements CaretModel, PrioritizedDocumentListener,
 
   @Override
   public boolean removeCaret(@NotNull Caret caret) {
-    myEditor.assertIsDispatchThread();
+    EditorImpl.assertIsDispatchThread();
     if (myCarets.size() <= 1 || !(caret instanceof CaretImpl)) {
       return false;
     }
@@ -307,7 +307,7 @@ public class CaretModelImpl implements CaretModel, PrioritizedDocumentListener,
 
   @Override
   public void removeSecondaryCarets() {
-    myEditor.assertIsDispatchThread();
+    EditorImpl.assertIsDispatchThread();
     if (!supportsMultipleCarets()) {
       return;
     }
@@ -329,7 +329,7 @@ public class CaretModelImpl implements CaretModel, PrioritizedDocumentListener,
 
   @Override
   public void runForEachCaret(@NotNull final CaretAction action, final boolean reverseOrder) {
-    myEditor.assertIsDispatchThread();
+    EditorImpl.assertIsDispatchThread();
     if (!supportsMultipleCarets()) {
       action.perform(getPrimaryCaret());
       return;
@@ -358,7 +358,7 @@ public class CaretModelImpl implements CaretModel, PrioritizedDocumentListener,
 
   @Override
   public void runBatchCaretOperation(@NotNull Runnable runnable) {
-    myEditor.assertIsDispatchThread();
+    EditorImpl.assertIsDispatchThread();
     doWithCaretMerging(runnable);
   }
 
@@ -442,7 +442,7 @@ public class CaretModelImpl implements CaretModel, PrioritizedDocumentListener,
 
   @Override
   public void setCaretsAndSelections(@NotNull final List<CaretState> caretStates, final boolean updateSystemSelection) {
-    myEditor.assertIsDispatchThread();
+    EditorImpl.assertIsDispatchThread();
     if (caretStates.isEmpty()) {
       throw new IllegalArgumentException("At least one caret should exist");
     }
diff --git a/platform/platform-impl/src/com/intellij/ui/TableExpandableItemsHandler.java b/platform/platform-impl/src/com/intellij/ui/TableExpandableItemsHandler.java
index 6099561c7283..26d9908c932c 100644
--- a/platform/platform-impl/src/com/intellij/ui/TableExpandableItemsHandler.java
+++ b/platform/platform-impl/src/com/intellij/ui/TableExpandableItemsHandler.java
@@ -23,6 +23,7 @@ import javax.swing.event.ListSelectionEvent;
 import javax.swing.event.ListSelectionListener;
 import javax.swing.event.TableModelEvent;
 import javax.swing.event.TableModelListener;
+import javax.swing.table.JTableHeader;
 import javax.swing.table.TableColumnModel;
 import javax.swing.table.TableModel;
 import java.awt.*;
@@ -110,7 +111,8 @@ public class TableExpandableItemsHandler extends AbstractExpandableItemsHandler<
   public Pair<Component, Rectangle> getCellRendererAndBounds(TableCell key) {
     if (key.row < 0 || key.row >= myComponent.getRowCount() ||
         key.column < 0 || key.column >= myComponent.getColumnCount() ||
-        key.row == myComponent.getEditingRow() && key.column == myComponent.getEditingColumn()) {
+        key.row == myComponent.getEditingRow() && key.column == myComponent.getEditingColumn() ||
+        hasDraggingOrResizingColumn()) {
       return null;
     }
 
@@ -143,4 +145,9 @@ public class TableExpandableItemsHandler extends AbstractExpandableItemsHandler<
 
     return new TableCell(rowIndex, columnIndex);
   }
+
+  private boolean hasDraggingOrResizingColumn() {
+    JTableHeader header = myComponent.getTableHeader();
+    return header != null && (header.getResizingColumn() != null || header.getDraggedColumn() != null);
+  }
 }
diff --git a/platform/vcs-impl/src/com/intellij/openapi/vcs/roots/VcsRootProblemNotifier.java b/platform/vcs-impl/src/com/intellij/openapi/vcs/roots/VcsRootProblemNotifier.java
index c720834fa594..0bae5907771e 100644
--- a/platform/vcs-impl/src/com/intellij/openapi/vcs/roots/VcsRootProblemNotifier.java
+++ b/platform/vcs-impl/src/com/intellij/openapi/vcs/roots/VcsRootProblemNotifier.java
@@ -37,7 +37,6 @@ import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 import javax.swing.event.HyperlinkEvent;
-import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
 import java.util.Set;
@@ -83,17 +82,16 @@ public class VcsRootProblemNotifier {
       return;
     }
 
-    Collection<VcsRootError> unregisteredRoots = getUnregisteredRoots(errors);
-    Collection<VcsRootError> important = getImportantMappings(unregisteredRoots);
+    Collection<VcsRootError> importantUnregisteredRoots = getImportantUnregisteredMappings(errors);
     Collection<VcsRootError> invalidRoots = getInvalidRoots(errors);
 
-    if (invalidRoots.isEmpty() && (important.isEmpty() || myReportedUnregisteredRoots.containsAll(important))) {
+    if (invalidRoots.isEmpty() && (importantUnregisteredRoots.isEmpty() || myReportedUnregisteredRoots.containsAll(importantUnregisteredRoots))) {
       return;
     }
-    myReportedUnregisteredRoots.addAll(unregisteredRoots);
+    myReportedUnregisteredRoots.addAll(importantUnregisteredRoots);
 
-    String title = makeTitle(unregisteredRoots, invalidRoots);
-    String description = makeDescription(unregisteredRoots, invalidRoots);
+    String title = makeTitle(importantUnregisteredRoots, invalidRoots);
+    String description = makeDescription(importantUnregisteredRoots, invalidRoots);
 
     synchronized (NOTIFICATION_LOCK) {
       expireNotification();
@@ -105,17 +103,6 @@ public class VcsRootProblemNotifier {
     }
   }
 
-  @NotNull
-  private List<VcsRootError> getImportantMappings(@NotNull Collection<VcsRootError> unregisteredRoots) {
-    return ContainerUtil.filter(unregisteredRoots, new Condition<VcsRootError>() {
-      @Override
-      public boolean value(VcsRootError error) {
-        String mapping = error.getMapping();
-        return isUnderProjectDir(mapping) && !isIgnored(mapping);
-      }
-    });
-  }
-
   private boolean isUnderProjectDir(@NotNull String mapping) {
     return mapping.equals(VcsDirectoryMapping.PROJECT_CONSTANT) || FileUtil.isAncestor(myProject.getBasePath(), mapping, false);
   }
@@ -207,24 +194,24 @@ public class VcsRootProblemNotifier {
   }
 
   @NotNull
-  private static Collection<VcsRootError> getUnregisteredRoots(@NotNull Collection<VcsRootError> errors) {
-    return filterErrorsByType(errors, VcsRootError.Type.UNREGISTERED_ROOT);
+  private List<VcsRootError> getImportantUnregisteredMappings(@NotNull Collection<VcsRootError> errors) {
+    return ContainerUtil.filter(errors, new Condition<VcsRootError>() {
+      @Override
+      public boolean value(VcsRootError error) {
+        String mapping = error.getMapping();
+        return error.getType() == VcsRootError.Type.UNREGISTERED_ROOT && isUnderProjectDir(mapping) && !isIgnored(mapping);
+      }
+    });
   }
 
   @NotNull
   private static Collection<VcsRootError> getInvalidRoots(@NotNull Collection<VcsRootError> errors) {
-    return filterErrorsByType(errors, VcsRootError.Type.EXTRA_MAPPING);
-  }
-
-  @NotNull
-  private static Collection<VcsRootError> filterErrorsByType(@NotNull Collection<VcsRootError> errors, @NotNull VcsRootError.Type type) {
-    Collection<VcsRootError> roots = new ArrayList<VcsRootError>();
-    for (VcsRootError error : errors) {
-      if (error.getType() == type) {
-        roots.add(error);
+    return ContainerUtil.filter(errors, new Condition<VcsRootError>() {
+      @Override
+      public boolean value(VcsRootError error) {
+        return error.getType() == VcsRootError.Type.EXTRA_MAPPING;
       }
-    }
-    return roots;
+    });
   }
 
   private static class MyNotificationListener implements NotificationListener {