diff --git a/apps/opencs/view/render/cell.cpp b/apps/opencs/view/render/cell.cpp
index b0c8425ad3..f2c851cc72 100644
--- a/apps/opencs/view/render/cell.cpp
+++ b/apps/opencs/view/render/cell.cpp
@@ -612,7 +612,7 @@ osg::ref_ptr<CSVRender::TagBase> CSVRender::Cell::getSnapTarget(unsigned int ele
     return result;
 }
 
-void CSVRender::Cell::selectFromGroup(const std::vector<std::string> group)
+void CSVRender::Cell::selectFromGroup(const std::vector<std::string>& group)
 {
     for (const auto& [_, object] : mObjects)
     {
diff --git a/apps/opencs/view/render/cell.hpp b/apps/opencs/view/render/cell.hpp
index 52e01c631a..5bfce47904 100644
--- a/apps/opencs/view/render/cell.hpp
+++ b/apps/opencs/view/render/cell.hpp
@@ -148,7 +148,7 @@ namespace CSVRender
         // already selected
         void selectAllWithSameParentId(int elementMask);
 
-        void selectFromGroup(const std::vector<std::string> group);
+        void selectFromGroup(const std::vector<std::string>& group);
 
         void unhideAll();
 
diff --git a/apps/opencs/view/render/object.cpp b/apps/opencs/view/render/object.cpp
index 0e114ac06e..4ad1aaca15 100644
--- a/apps/opencs/view/render/object.cpp
+++ b/apps/opencs/view/render/object.cpp
@@ -484,7 +484,7 @@ CSVRender::Object::~Object()
     mParentNode->removeChild(mRootNode);
 }
 
-void CSVRender::Object::setSelected(bool selected, osg::Vec4f color)
+void CSVRender::Object::setSelected(bool selected, const osg::Vec4f& color)
 {
     mSelected = selected;
 
diff --git a/apps/opencs/view/render/object.hpp b/apps/opencs/view/render/object.hpp
index 9b18b99561..5c73b12211 100644
--- a/apps/opencs/view/render/object.hpp
+++ b/apps/opencs/view/render/object.hpp
@@ -139,7 +139,7 @@ namespace CSVRender
         ~Object();
 
         /// Mark the object as selected, selected objects show an outline effect
-        void setSelected(bool selected, osg::Vec4f color = osg::Vec4f(1, 1, 1, 1));
+        void setSelected(bool selected, const osg::Vec4f& color = osg::Vec4f(1, 1, 1, 1));
 
         bool getSelected() const;
 
diff --git a/apps/opencs/view/render/pagedworldspacewidget.cpp b/apps/opencs/view/render/pagedworldspacewidget.cpp
index fab706e3ca..3d5c6fe565 100644
--- a/apps/opencs/view/render/pagedworldspacewidget.cpp
+++ b/apps/opencs/view/render/pagedworldspacewidget.cpp
@@ -875,7 +875,7 @@ std::vector<osg::ref_ptr<CSVRender::TagBase>> CSVRender::PagedWorldspaceWidget::
     return result;
 }
 
-void CSVRender::PagedWorldspaceWidget::selectGroup(std::vector<std::string> group) const
+void CSVRender::PagedWorldspaceWidget::selectGroup(const std::vector<std::string>& group) const
 {
     for (const auto& [_, cell] : mCells)
         cell->selectFromGroup(group);
diff --git a/apps/opencs/view/render/pagedworldspacewidget.hpp b/apps/opencs/view/render/pagedworldspacewidget.hpp
index 3d2ab97e89..744cc7ccb9 100644
--- a/apps/opencs/view/render/pagedworldspacewidget.hpp
+++ b/apps/opencs/view/render/pagedworldspacewidget.hpp
@@ -163,7 +163,7 @@ namespace CSVRender
 
         std::vector<osg::ref_ptr<TagBase>> getSelection(unsigned int elementMask) const override;
 
-        void selectGroup(const std::vector<std::string> group) const override;
+        void selectGroup(const std::vector<std::string>& group) const override;
 
         void unhideAll() const override;
 
diff --git a/apps/opencs/view/render/unpagedworldspacewidget.cpp b/apps/opencs/view/render/unpagedworldspacewidget.cpp
index ea99294c28..899918c3b9 100644
--- a/apps/opencs/view/render/unpagedworldspacewidget.cpp
+++ b/apps/opencs/view/render/unpagedworldspacewidget.cpp
@@ -199,7 +199,7 @@ std::vector<osg::ref_ptr<CSVRender::TagBase>> CSVRender::UnpagedWorldspaceWidget
     return mCell->getSelection(elementMask);
 }
 
-void CSVRender::UnpagedWorldspaceWidget::selectGroup(const std::vector<std::string> group) const
+void CSVRender::UnpagedWorldspaceWidget::selectGroup(const std::vector<std::string>& group) const
 {
     mCell->selectFromGroup(group);
 }
diff --git a/apps/opencs/view/render/unpagedworldspacewidget.hpp b/apps/opencs/view/render/unpagedworldspacewidget.hpp
index 22a0475fe2..89c916415d 100644
--- a/apps/opencs/view/render/unpagedworldspacewidget.hpp
+++ b/apps/opencs/view/render/unpagedworldspacewidget.hpp
@@ -93,7 +93,7 @@ namespace CSVRender
 
         std::vector<osg::ref_ptr<TagBase>> getSelection(unsigned int elementMask) const override;
 
-        void selectGroup(const std::vector<std::string> group) const override;
+        void selectGroup(const std::vector<std::string>& group) const override;
 
         void unhideAll() const override;
 
diff --git a/apps/opencs/view/render/worldspacewidget.hpp b/apps/opencs/view/render/worldspacewidget.hpp
index a6d87440f1..505d985ffa 100644
--- a/apps/opencs/view/render/worldspacewidget.hpp
+++ b/apps/opencs/view/render/worldspacewidget.hpp
@@ -201,7 +201,7 @@ namespace CSVRender
 
         virtual std::vector<osg::ref_ptr<TagBase>> getSelection(unsigned int elementMask) const = 0;
 
-        virtual void selectGroup(const std::vector<std::string>) const = 0;
+        virtual void selectGroup(const std::vector<std::string>&) const = 0;
 
         virtual void unhideAll() const = 0;