diff --git a/src/app/color_picker.cpp b/src/app/color_picker.cpp
index 477ca6c78..e3c98c75c 100644
--- a/src/app/color_picker.cpp
+++ b/src/app/color_picker.cpp
@@ -34,7 +34,7 @@ ColorPicker::ColorPicker()
 {
 }
 
-void ColorPicker::pickColor(DocumentLocation& location, int x, int y, Mode mode)
+void ColorPicker::pickColor(const DocumentLocation& location, int x, int y, Mode mode)
 {
   m_alpha = 255;
   m_color = app::Color::fromMask();
diff --git a/src/app/color_picker.h b/src/app/color_picker.h
index 2da79cae2..7a7a109d7 100644
--- a/src/app/color_picker.h
+++ b/src/app/color_picker.h
@@ -30,7 +30,7 @@ namespace app {
 
     ColorPicker();
 
-    void pickColor(DocumentLocation& location, int x, int y, Mode mode);
+    void pickColor(const DocumentLocation& location, int x, int y, Mode mode);
 
     app::Color color() const { return m_color; }
     int alpha() const { return m_alpha; }