diff --git a/Core/GDCore/Events/CodeGeneration/ExpressionCodeGenerator.cpp b/Core/GDCore/Events/CodeGeneration/ExpressionCodeGenerator.cpp
index 86aca52b5f..e0d327b6eb 100644
--- a/Core/GDCore/Events/CodeGeneration/ExpressionCodeGenerator.cpp
+++ b/Core/GDCore/Events/CodeGeneration/ExpressionCodeGenerator.cpp
@@ -55,6 +55,7 @@ gd::String ExpressionCodeGenerator::GenerateExpressionCode(
   gd::ExpressionValidator validator(codeGenerator.GetPlatform(),
                                     codeGenerator.GetProjectScopedContainers(),
                                     rootType,
+                                    rootObjectName,
                                     extraInfo);
   node->Visit(validator);
   if (!validator.GetFatalErrors().empty()) {
diff --git a/Core/GDCore/IDE/Events/EventsBehaviorRenamer.cpp b/Core/GDCore/IDE/Events/EventsBehaviorRenamer.cpp
index 6e97c89ea7..a450aa71ac 100644
--- a/Core/GDCore/IDE/Events/EventsBehaviorRenamer.cpp
+++ b/Core/GDCore/IDE/Events/EventsBehaviorRenamer.cpp
@@ -15,7 +15,6 @@
 #include "GDCore/Events/Parsers/ExpressionParser2NodeWorker.h"
 #include "GDCore/Extensions/Metadata/MetadataProvider.h"
 #include "GDCore/Extensions/Metadata/ParameterMetadataTools.h"
-#include "GDCore/IDE/Events/ExpressionValidator.h"
 #include "GDCore/Project/Layout.h"
 #include "GDCore/Project/Project.h"
 #include "GDCore/String.h"
diff --git a/Core/GDCore/IDE/Events/EventsContextAnalyzer.cpp b/Core/GDCore/IDE/Events/EventsContextAnalyzer.cpp
index 58aac2059c..8c209dcbb1 100644
--- a/Core/GDCore/IDE/Events/EventsContextAnalyzer.cpp
+++ b/Core/GDCore/IDE/Events/EventsContextAnalyzer.cpp
@@ -15,7 +15,6 @@
 #include "GDCore/Extensions/Metadata/InstructionMetadata.h"
 #include "GDCore/Extensions/Metadata/MetadataProvider.h"
 #include "GDCore/Extensions/Metadata/ParameterMetadataTools.h"
-#include "GDCore/IDE/Events/ExpressionValidator.h"
 #include "GDCore/IDE/Events/ExpressionTypeFinder.h"
 #include "GDCore/Project/Layout.h"
 #include "GDCore/Project/Project.h"
diff --git a/Core/GDCore/IDE/Events/EventsParameterReplacer.cpp b/Core/GDCore/IDE/Events/EventsParameterReplacer.cpp
index 9a3e800d38..b6cab33443 100644
--- a/Core/GDCore/IDE/Events/EventsParameterReplacer.cpp
+++ b/Core/GDCore/IDE/Events/EventsParameterReplacer.cpp
@@ -18,7 +18,6 @@
 #include "GDCore/Extensions/Metadata/MetadataProvider.h"
 #include "GDCore/Extensions/Metadata/ParameterMetadata.h"
 #include "GDCore/Extensions/Metadata/ParameterMetadataTools.h"
-#include "GDCore/IDE/Events/ExpressionValidator.h"
 #include "GDCore/Project/Layout.h"
 #include "GDCore/Project/Project.h"
 #include "GDCore/Project/ProjectScopedContainers.h"
diff --git a/Core/GDCore/IDE/Events/EventsPropertyReplacer.cpp b/Core/GDCore/IDE/Events/EventsPropertyReplacer.cpp
index 7783f7d74a..ac5ce5ce7c 100644
--- a/Core/GDCore/IDE/Events/EventsPropertyReplacer.cpp
+++ b/Core/GDCore/IDE/Events/EventsPropertyReplacer.cpp
@@ -18,7 +18,6 @@
 #include "GDCore/Extensions/Metadata/MetadataProvider.h"
 #include "GDCore/Extensions/Metadata/ParameterMetadata.h"
 #include "GDCore/Extensions/Metadata/ParameterMetadataTools.h"
-#include "GDCore/IDE/Events/ExpressionValidator.h"
 #include "GDCore/Project/Layout.h"
 #include "GDCore/Project/Project.h"
 #include "GDCore/Project/ProjectScopedContainers.h"
diff --git a/Core/GDCore/IDE/Events/EventsVariableInstructionTypeSwitcher.cpp b/Core/GDCore/IDE/Events/EventsVariableInstructionTypeSwitcher.cpp
index 974c3f3cc0..73eb2fff79 100644
--- a/Core/GDCore/IDE/Events/EventsVariableInstructionTypeSwitcher.cpp
+++ b/Core/GDCore/IDE/Events/EventsVariableInstructionTypeSwitcher.cpp
@@ -18,7 +18,6 @@
 #include "GDCore/Extensions/Metadata/MetadataProvider.h"
 #include "GDCore/Extensions/Metadata/ParameterMetadata.h"
 #include "GDCore/Extensions/Metadata/ParameterMetadataTools.h"
-#include "GDCore/IDE/Events/ExpressionValidator.h"
 #include "GDCore/IDE/Events/ExpressionVariableOwnerFinder.h"
 #include "GDCore/IDE/Events/ExpressionVariableNameFinder.h"
 #include "GDCore/IDE/VariableInstructionSwitcher.h"
diff --git a/Core/GDCore/IDE/Events/EventsVariableReplacer.cpp b/Core/GDCore/IDE/Events/EventsVariableReplacer.cpp
index cc3dabb4bb..ab18332ffc 100644
--- a/Core/GDCore/IDE/Events/EventsVariableReplacer.cpp
+++ b/Core/GDCore/IDE/Events/EventsVariableReplacer.cpp
@@ -18,7 +18,6 @@
 #include "GDCore/Extensions/Metadata/MetadataProvider.h"
 #include "GDCore/Extensions/Metadata/ParameterMetadata.h"
 #include "GDCore/Extensions/Metadata/ParameterMetadataTools.h"
-#include "GDCore/IDE/Events/ExpressionValidator.h"
 #include "GDCore/IDE/Events/ExpressionVariableOwnerFinder.h"
 #include "GDCore/IDE/Events/ExpressionVariableNameFinder.h"
 #include "GDCore/IDE/VariableInstructionSwitcher.h"
diff --git a/Core/GDCore/IDE/Events/ExpressionValidator.cpp b/Core/GDCore/IDE/Events/ExpressionValidator.cpp
index 672431985d..8de5525381 100644
--- a/Core/GDCore/IDE/Events/ExpressionValidator.cpp
+++ b/Core/GDCore/IDE/Events/ExpressionValidator.cpp
@@ -392,6 +392,12 @@ ExpressionValidator::Type ExpressionValidator::ValidateFunction(
     return returnType;
   }
 
+  const gd::String parentRootObjectName = rootObjectName;
+  // We don't check objectvar parameters since they are only used by the legacy
+  // functions like: `Object.Variable(MyVariable)` which allow undeclared
+  // variables.
+  rootObjectName = emptyParameterExtraInfo;
+
   // TODO: reverse the order of diagnostic?
   size_t writtenParametersFirstIndex =
       ExpressionParser2::WrittenParametersFirstIndex(function.objectName,
@@ -452,6 +458,7 @@ ExpressionValidator::Type ExpressionValidator::ValidateFunction(
     }
     metadataIndex++;
   }
+  rootObjectName = parentRootObjectName;
   return returnType;
 }
 
diff --git a/Core/GDCore/IDE/Events/ExpressionValidator.h b/Core/GDCore/IDE/Events/ExpressionValidator.h
index 27ada25ad2..869ff537f4 100644
--- a/Core/GDCore/IDE/Events/ExpressionValidator.h
+++ b/Core/GDCore/IDE/Events/ExpressionValidator.h
@@ -40,10 +40,12 @@ class GD_CORE_API ExpressionValidator : public ExpressionParser2NodeWorker {
   ExpressionValidator(const gd::Platform &platform_,
                       const gd::ProjectScopedContainers & projectScopedContainers_,
                       const gd::String &rootType_,
+                      const gd::String &rootObjectName_ = emptyParameterExtraInfo,
                       const gd::String &extraInfo_ = emptyParameterExtraInfo)
       : platform(platform_),
         projectScopedContainers(projectScopedContainers_),
         parentType(StringToType(gd::ValueTypeMetadata::GetExpressionPrimitiveValueType(rootType_))),
+        rootObjectName(rootObjectName_),
         childType(Type::Unknown),
         forbidsUsageOfBracketsBecauseParentIsObject(false),
         currentParameterExtraInfo(&extraInfo_),
@@ -593,6 +595,8 @@ private:
   std::vector<std::unique_ptr<ExpressionParserError>> supplementalErrors;
   Type childType; ///< The type "discovered" down the tree and passed up.
   Type parentType; ///< The type "required" by the top of the tree.
+  /** The root object name of the expression or a function call. */
+  gd::String rootObjectName;
   bool forbidsUsageOfBracketsBecauseParentIsObject;
   gd::String variableObjectName;
   gd::ExpressionParserLocation variableObjectNameLocation;
diff --git a/Core/GDCore/IDE/Events/ExpressionsParameterMover.cpp b/Core/GDCore/IDE/Events/ExpressionsParameterMover.cpp
index 7eb6e23c1c..bf2a6d848b 100644
--- a/Core/GDCore/IDE/Events/ExpressionsParameterMover.cpp
+++ b/Core/GDCore/IDE/Events/ExpressionsParameterMover.cpp
@@ -14,7 +14,6 @@
 #include "GDCore/Events/Parsers/ExpressionParser2NodePrinter.h"
 #include "GDCore/Events/Parsers/ExpressionParser2NodeWorker.h"
 #include "GDCore/Extensions/Metadata/MetadataProvider.h"
-#include "GDCore/IDE/Events/ExpressionValidator.h"
 #include "GDCore/Project/Layout.h"
 #include "GDCore/Project/Project.h"
 #include "GDCore/String.h"
diff --git a/Core/GDCore/IDE/Events/ExpressionsRenamer.cpp b/Core/GDCore/IDE/Events/ExpressionsRenamer.cpp
index b0382ad322..e973d25894 100644
--- a/Core/GDCore/IDE/Events/ExpressionsRenamer.cpp
+++ b/Core/GDCore/IDE/Events/ExpressionsRenamer.cpp
@@ -14,7 +14,6 @@
 #include "GDCore/Events/Parsers/ExpressionParser2NodePrinter.h"
 #include "GDCore/Events/Parsers/ExpressionParser2NodeWorker.h"
 #include "GDCore/Extensions/Metadata/MetadataProvider.h"
-#include "GDCore/IDE/Events/ExpressionValidator.h"
 #include "GDCore/Project/Layout.h"
 #include "GDCore/Project/Project.h"
 #include "GDCore/String.h"
diff --git a/Core/GDCore/IDE/Events/ProjectElementRenamer.cpp b/Core/GDCore/IDE/Events/ProjectElementRenamer.cpp
index a8fc2d4115..6374da7b17 100644
--- a/Core/GDCore/IDE/Events/ProjectElementRenamer.cpp
+++ b/Core/GDCore/IDE/Events/ProjectElementRenamer.cpp
@@ -15,7 +15,6 @@
 #include "GDCore/Events/Parsers/ExpressionParser2NodeWorker.h"
 #include "GDCore/Extensions/Metadata/MetadataProvider.h"
 #include "GDCore/Extensions/Metadata/ParameterMetadataTools.h"
-#include "GDCore/IDE/Events/ExpressionValidator.h"
 #include "GDCore/Project/Layout.h"
 #include "GDCore/Project/Project.h"
 #include "GDCore/String.h"
diff --git a/Core/GDCore/IDE/InstructionValidator.cpp b/Core/GDCore/IDE/InstructionValidator.cpp
index 5608df5af2..1f7c35446e 100644
--- a/Core/GDCore/IDE/InstructionValidator.cpp
+++ b/Core/GDCore/IDE/InstructionValidator.cpp
@@ -65,10 +65,23 @@ ParameterValidationResult InstructionValidator::ValidateParameter(
   if (gd::ParameterMetadata::IsExpression("number", parameterType) ||
       gd::ParameterMetadata::IsExpression("string", parameterType) ||
       gd::ParameterMetadata::IsExpression("variable", parameterType)) {
+
+    // New object variable instructions require the variable to be
+    // declared while legacy ones don't.
+    // For legacy variable instruction, we pass an empty object name.
+    gd::String rootObjectName = "";
+    if (parameterType == "objectvar" &&
+        gd::VariableInstructionSwitcher::IsSwitchableVariableInstruction(
+            instruction.GetType())) {
+      const auto &objectsContainersList =
+          projectScopedContainers.GetObjectsContainersList();
+      rootObjectName = instruction.GetParameter(0).GetPlainString();
+    }
     auto &expressionNode =
         *instruction.GetParameter(parameterIndex).GetRootNode();
     ExpressionValidator expressionValidator(platform, projectScopedContainers,
                                             parameterType,
+                                            rootObjectName,
                                             parameterMetadata.GetExtraInfo());
     expressionNode.Visit(expressionValidator);
 
@@ -78,27 +91,6 @@ ParameterValidationResult InstructionValidator::ValidateParameter(
     if (!expressionValidator.GetDeprecationWarnings().empty()) {
       result.hasDeprecationWarning = true;
     }
-
-    // New object variable instructions require the variable to be
-    // declared while legacy ones don't.
-    // This is why it's done here instead of in the parser directly.
-    if (result.isValid && parameterType == "objectvar" &&
-        gd::VariableInstructionSwitcher::IsSwitchableVariableInstruction(
-            instruction.GetType())) {
-      // Check at least the name of the root variable, it's the best we can
-      // do.
-      const auto &objectsContainersList =
-          projectScopedContainers.GetObjectsContainersList();
-      const auto &objectName = instruction.GetParameter(0).GetPlainString();
-      const auto &variableName =
-          instruction.GetParameter(parameterIndex).GetPlainString();
-      if (objectsContainersList.HasObjectOrGroupWithVariableNamed(
-              objectName,
-              gd::InstructionValidator::GetRootVariableName(variableName)) ==
-          gd::ObjectsContainersList::DoesNotExist) {
-        result.isValid = false;
-      }
-    }
   } else if (gd::ParameterMetadata::IsObject(parameterType)) {
     const auto &objectOrGroupName =
         instruction.GetParameter(parameterIndex).GetPlainString();
diff --git a/Core/tests/DummyPlatform.cpp b/Core/tests/DummyPlatform.cpp
index 9e888804d4..56a0ee8e51 100644
--- a/Core/tests/DummyPlatform.cpp
+++ b/Core/tests/DummyPlatform.cpp
@@ -5,7 +5,6 @@
  */
 #include "GDCore/Extensions/Platform.h"
 #include "GDCore/Extensions/PlatformExtension.h"
-#include "GDCore/IDE/Events/ExpressionValidator.h"
 #include "GDCore/Project/Behavior.h"
 #include "GDCore/Project/ObjectConfiguration.h"
 #include "GDCore/Extensions/Builtin/SpriteExtension/SpriteObject.h"
diff --git a/Core/tests/ExpressionParser2NaugtyStrings.cpp b/Core/tests/ExpressionParser2NaugtyStrings.cpp
index 3a44004e5e..5fe6ab2ced 100644
--- a/Core/tests/ExpressionParser2NaugtyStrings.cpp
+++ b/Core/tests/ExpressionParser2NaugtyStrings.cpp
@@ -8,7 +8,6 @@
 #include "DummyPlatform.h"
 #include "GDCore/Extensions/Platform.h"
 #include "GDCore/Extensions/PlatformExtension.h"
-#include "GDCore/IDE/Events/ExpressionValidator.h"
 #include "GDCore/Project/Layout.h"
 #include "GDCore/Project/Project.h"
 #include "catch.hpp"
diff --git a/Core/tests/ExpressionParser2NodePrinter.cpp b/Core/tests/ExpressionParser2NodePrinter.cpp
index 5638a7b387..7fe9d0a9a8 100644
--- a/Core/tests/ExpressionParser2NodePrinter.cpp
+++ b/Core/tests/ExpressionParser2NodePrinter.cpp
@@ -8,7 +8,6 @@
 #include "GDCore/Events/Parsers/ExpressionParser2.h"
 #include "GDCore/Extensions/Platform.h"
 #include "GDCore/Extensions/PlatformExtension.h"
-#include "GDCore/IDE/Events/ExpressionValidator.h"
 #include "GDCore/Project/Layout.h"
 #include "GDCore/Project/Project.h"
 #include "catch.hpp"