diff --git a/src/app/commands/cmd_clear.cpp b/src/app/commands/cmd_clear.cpp
index 437d67fd3b..30e8bf7ecc 100644
--- a/src/app/commands/cmd_clear.cpp
+++ b/src/app/commands/cmd_clear.cpp
@@ -78,6 +78,10 @@ void ClearCommand::onExecute(Context* context)
   ContextWriter writer(context);
   Document* document = writer.document();
   bool visibleMask = document->isMaskVisible();
+
+  if (!writer.cel())
+    return;
+
   {
     UndoTransaction undoTransaction(writer.context(), "Clear");
     DocumentApi api = document->getApi();
diff --git a/src/app/document_api.cpp b/src/app/document_api.cpp
index 48b0b175cf..3e8cc2c361 100644
--- a/src/app/document_api.cpp
+++ b/src/app/document_api.cpp
@@ -1097,8 +1097,10 @@ void DocumentApi::replaceStockImage(Sprite* sprite, int imageIndex, Image* newIm
 // Clears the mask region in the current sprite with the specified background color.
 void DocumentApi::clearMask(Layer* layer, Cel* cel, color_t bgcolor)
 {
+  ASSERT(cel);
   ASSERT(layer == cel->layer());
-  Image* image = cel->image();
+
+  Image* image = (cel ? cel->image(): NULL);
   if (!image)
     return;