diff --git a/src/plugins/qmldesigner/designercore/projectstorage/projectstorage.h b/src/plugins/qmldesigner/designercore/projectstorage/projectstorage.h
index e8edd79b1ba..22306e8c0db 100644
--- a/src/plugins/qmldesigner/designercore/projectstorage/projectstorage.h
+++ b/src/plugins/qmldesigner/designercore/projectstorage/projectstorage.h
@@ -63,8 +63,12 @@ public:
         TypeIds updatedTypeIds;
         updatedTypeIds.reserve(types.size());
 
-        for (auto &&type : types)
+        for (auto &&type : types) {
+            if (!type.sourceId)
+                throw TypeHasInvalidSourceId{};
+
             updatedTypeIds.push_back(syncType(type));
+        }
 
         deleteNotUpdatedTypes(updatedTypeIds, sourceIds);
 
@@ -262,8 +266,17 @@ private:
             return &sourceId;
         });
 
-        deleteNotUpdatedTypesInSourcesStatement.write(Utils::span(sourceIdValues),
-                                                      Utils::span(updatedTypeIdValues));
+        auto removedTypeIds = selectNotUpdatedTypesInSourcesStatement.template range<TypeId>(
+            Utils::span(sourceIdValues), Utils::span(updatedTypeIdValues));
+
+        for (TypeId typeId : removedTypeIds) {
+            resetTypeStatement.write(&typeId);
+            deleteExportTypesByTypeIdStatement.write(&typeId);
+            deleteEnumerationDeclarationByTypeIdStatement.write(&typeId);
+            deletePropertyDeclarationByTypeIdStatement.write(&typeId);
+            deleteFunctionDeclarationByTypeIdStatement.write(&typeId);
+            deleteSignalDeclarationByTypeIdStatement.write(&typeId);
+        }
     }
 
     void upsertExportedType(Utils::SmallStringView qualifiedName, Storage::Version version, TypeId typeId)
@@ -689,7 +702,6 @@ private:
                                       Sqlite::ForeignKeyAction::Restrict,
                                       Sqlite::ForeignKeyAction::Restrict,
                                       Sqlite::Enforment::Deferred);
-            table.addColumn("defaultProperty");
 
             table.addUniqueIndex({nameColumn});
 
@@ -864,9 +876,21 @@ public:
         "SELECT name, typeId, (SELECT name FROM types WHERE typeId=outerTypes.prototypeId),"
         "accessSemantics, ifnull(sourceId, -1) FROM types AS outerTypes",
         database};
-    WriteStatement deleteNotUpdatedTypesInSourcesStatement{
-        "DELETE FROM types WHERE (sourceId IN carray(?1) AND typeId NOT IN carray(?2)) OR sourceId "
-        "IS NULL",
+    ReadStatement<1> selectNotUpdatedTypesInSourcesStatement{
+        "SELECT typeId FROM types WHERE (sourceId IN carray(?1) AND typeId NOT IN carray(?2))",
+        database};
+    WriteStatement deleteExportTypesByTypeIdStatement{"DELETE FROM exportedTypes WHERE typeId=?",
+                                                      database};
+    WriteStatement deleteEnumerationDeclarationByTypeIdStatement{
+        "DELETE FROM enumerationDeclarations WHERE typeId=?", database};
+    WriteStatement deletePropertyDeclarationByTypeIdStatement{
+        "DELETE FROM propertyDeclarations WHERE typeId=?", database};
+    WriteStatement deleteFunctionDeclarationByTypeIdStatement{
+        "DELETE FROM functionDeclarations WHERE typeId=?", database};
+    WriteStatement deleteSignalDeclarationByTypeIdStatement{
+        "DELETE FROM signalDeclarations WHERE typeId=?", database};
+    WriteStatement resetTypeStatement{
+        "UPDATE types SET accessSemantics=NULL, sourceId=NULL, prototypeId=NULL WHERE typeId=?",
         database};
     mutable ReadStatement<3> selectPropertyDeclarationsByTypeIdStatement{
         "SELECT name, (SELECT name FROM types WHERE typeId=propertyDeclarations.propertyTypeId),"
diff --git a/src/plugins/qmldesigner/designercore/projectstorage/projectstorageexceptions.h b/src/plugins/qmldesigner/designercore/projectstorage/projectstorageexceptions.h
index 3fb31f566a6..5204512c9e4 100644
--- a/src/plugins/qmldesigner/designercore/projectstorage/projectstorageexceptions.h
+++ b/src/plugins/qmldesigner/designercore/projectstorage/projectstorageexceptions.h
@@ -65,4 +65,10 @@ public:
     }
 };
 
+class TypeHasInvalidSourceId : std::exception
+{
+public:
+    const char *what() const noexcept override { return "The source id is invalid!"; }
+};
+
 } // namespace QmlDesigner
diff --git a/tests/unit/unittest/projectstorage-test.cpp b/tests/unit/unittest/projectstorage-test.cpp
index 2733a0e81cc..7549256b919 100644
--- a/tests/unit/unittest/projectstorage-test.cpp
+++ b/tests/unit/unittest/projectstorage-test.cpp
@@ -82,6 +82,19 @@ MATCHER_P4(IsStorageType,
            && type.accessSemantics == accessSemantics && type.sourceId == sourceId;
 }
 
+MATCHER_P3(IsStorageTypeWithInvalidSourceId,
+           typeName,
+           prototype,
+           accessSemantics,
+           std::string(negation ? "isn't " : "is ")
+               + PrintToString(Storage::Type{typeName, prototype, accessSemantics, SourceId{}}))
+{
+    const Storage::Type &type = arg;
+
+    return type.typeName == typeName && type.prototype == prototype
+           && type.accessSemantics == accessSemantics && !type.sourceId.isValid();
+}
+
 MATCHER_P2(IsExportedType,
            qualifiedTypeName,
            version,
@@ -415,16 +428,6 @@ TEST_F(ProjectStorage,
     storage.fetchSourceContextId("/other/unknow/path");
 }
 
-TEST_F(ProjectStorage, SynchronizeTypesCalls)
-{
-    InSequence s;
-
-    EXPECT_CALL(databaseMock, immediateBegin());
-    EXPECT_CALL(databaseMock, commit());
-
-    storage.synchronizeTypes({}, {});
-}
-
 TEST_F(ProjectStorage, FetchTypeByTypeIdCalls)
 {
     InSequence s;
@@ -1271,8 +1274,9 @@ TEST_F(ProjectStorageSlowTest, SynchronizeTypesInsertTypeIntoPrototypeChain)
                                              IsExportedType("QtQuick.Item", Storage::Version{5, 15}))))));
 }
 
-TEST_F(ProjectStorageSlowTest, SynchronizeTypesThrowsForMissingPrototype)
+TEST_F(ProjectStorageSlowTest, SynchronizeTypesDontThrowsForMissingPrototype)
 {
+    sourceId1 = sourcePathCache.sourceId(path1);
     Storage::Types types{
         Storage::Type{"QQuickItem",
                       "QObject",
@@ -1280,19 +1284,10 @@ TEST_F(ProjectStorageSlowTest, SynchronizeTypesThrowsForMissingPrototype)
                       sourceId1,
                       {Storage::ExportedType{"QtQuick.Item", Storage::Version{5, 15}}}}};
 
-    ASSERT_THROW(storage.synchronizeTypes(types, {sourceId1}), Sqlite::ConstraintPreventsModification);
+    ASSERT_NO_THROW(storage.synchronizeTypes(types, {sourceId1}));
 }
 
-TEST_F(ProjectStorageSlowTest, SynchronizeTypesThrowsForWrongPrototypeChange)
-{
-    Storage::Types types{createTypes()};
-    storage.synchronizeTypes(types, {sourceId1, sourceId2});
-    types[0].prototype = "QQuickObject";
-
-    ASSERT_THROW(storage.synchronizeTypes(types, {sourceId1}), Sqlite::ConstraintPreventsModification);
-}
-
-TEST_F(ProjectStorageSlowTest, DontAddTypeWithInvalidSourceId)
+TEST_F(ProjectStorageSlowTest, TypeWithInvalidSourceIdThrows)
 {
     Storage::Types types{
         Storage::Type{"QQuickItem",
@@ -1301,9 +1296,51 @@ TEST_F(ProjectStorageSlowTest, DontAddTypeWithInvalidSourceId)
                       SourceId{},
                       {Storage::ExportedType{"QtQuick.Item", Storage::Version{5, 15}}}}};
 
-    storage.synchronizeTypes(types, {});
+    ASSERT_THROW(storage.synchronizeTypes(types, {}), QmlDesigner::TypeHasInvalidSourceId);
+}
 
-    ASSERT_THAT(storage.fetchTypes(), IsEmpty());
+TEST_F(ProjectStorageSlowTest, ResetsTypeIfTypeIsRemoved)
+{
+    Storage::Types types{createTypes()};
+    types[1].enumerationDeclarations = types[0].enumerationDeclarations;
+    types[1].propertyDeclarations = types[0].propertyDeclarations;
+    types[1].functionDeclarations = types[0].functionDeclarations;
+    types[1].signalDeclarations = types[0].signalDeclarations;
+    storage.synchronizeTypes(types, {sourceId1, sourceId2});
+    types.pop_back();
+
+    storage.synchronizeTypes(types, {sourceId1, sourceId2});
+
+    ASSERT_THAT(storage.fetchTypes(),
+                Contains(
+                    AllOf(IsStorageTypeWithInvalidSourceId("QObject", "", TypeAccessSemantics::Invalid),
+                          Field(&Storage::Type::exportedTypes, IsEmpty()),
+                          Field(&Storage::Type::enumerationDeclarations, IsEmpty()),
+                          Field(&Storage::Type::propertyDeclarations, IsEmpty()),
+                          Field(&Storage::Type::functionDeclarations, IsEmpty()),
+                          Field(&Storage::Type::signalDeclarations, IsEmpty()))));
+}
+
+TEST_F(ProjectStorageSlowTest, DontResetsTypeIfSourceIdIsNotSynchronized)
+{
+    Storage::Types types{createTypes()};
+    types[1].enumerationDeclarations = types[0].enumerationDeclarations;
+    types[1].propertyDeclarations = types[0].propertyDeclarations;
+    types[1].functionDeclarations = types[0].functionDeclarations;
+    types[1].signalDeclarations = types[0].signalDeclarations;
+    storage.synchronizeTypes(types, {sourceId1, sourceId2});
+    types.pop_back();
+
+    storage.synchronizeTypes(types, {sourceId1});
+
+    ASSERT_THAT(storage.fetchTypes(),
+                Contains(AllOf(IsStorageType("QObject", "", TypeAccessSemantics::Reference, sourceId2),
+                               Field(&Storage::Type::exportedTypes, Not(IsEmpty())),
+                               Field(&Storage::Type::exportedTypes, Not(IsEmpty())),
+                               Field(&Storage::Type::enumerationDeclarations, Not(IsEmpty())),
+                               Field(&Storage::Type::propertyDeclarations, Not(IsEmpty())),
+                               Field(&Storage::Type::functionDeclarations, Not(IsEmpty())),
+                               Field(&Storage::Type::signalDeclarations, Not(IsEmpty())))));
 }
 
 TEST_F(ProjectStorageSlowTest, SynchronizeTypesAddPropertyDeclarations)