diff --git a/Source/UI/Lists/UIListBoxEx.cpp b/Source/UI/Lists/UIListBoxEx.cpp
index 1c194a8cc..429598272 100644
--- a/Source/UI/Lists/UIListBoxEx.cpp
+++ b/Source/UI/Lists/UIListBoxEx.cpp
@@ -120,16 +120,6 @@ void UIListBoxEx::Refresh() {
   bar->Invalidate();
 }
 
-// INLINED
-int UIListBoxEx::LineAt(int x, int y) const {
-  if (x < 0 || y < 0 || x >= this->geometry.width || y >= this->geometry.height) {
-    return -1;
-  }
-
-  const int index = (this->topLine + y / this->lineHeight);
-  return index >= 0 && static_cast<unsigned>(index) < this->lines.size() ? index : -1;
-}
-
 // OFFSET: 0x008905A0
 // FUNCTION: fn_11419
 void UIListBoxEx::Slot25(int x, int y) {
diff --git a/Source/UI/Lists/UIListBoxEx.h b/Source/UI/Lists/UIListBoxEx.h
index 0ddd7c8e0..2edb888b2 100644
--- a/Source/UI/Lists/UIListBoxEx.h
+++ b/Source/UI/Lists/UIListBoxEx.h
@@ -51,6 +51,16 @@ protected:
   int LineAt(int x, int y) const;
 };
 
+// INLINED
+inline int UIListBoxEx::LineAt(int x, int y) const {
+  if (x < 0 || y < 0 || x >= this->geometry.width || y >= this->geometry.height) {
+    return -1;
+  }
+
+  const int index = (this->topLine + y / this->lineHeight);
+  return index >= 0 && static_cast<unsigned>(index) < this->lines.size() ? index : -1;
+}
+
 #if defined(_WIN32) && !defined(_WIN64)
 static_assert(sizeof(ExtendedListLine) == 28);
 static_assert(sizeof(UIListBoxEx) == 0xC0);