diff --git a/src/gui/widgets/listbox.cpp b/src/gui/widgets/listbox.cpp
index 35f2af7ebd4..6aa491a12ba 100644
--- a/src/gui/widgets/listbox.cpp
+++ b/src/gui/widgets/listbox.cpp
@@ -234,25 +234,6 @@ void tlistbox::list_item_clicked(twidget* caller)
 	assert(false);
 }
 
-bool tlistbox::update_content_size()
-{
-	if(get_visible() == twidget::INVISIBLE) {
-		return true;
-	}
-
-	if(get_size() == tpoint(0, 0)) {
-		return false;
-	}
-
-	if(content_resize_request(true)) {
-		content_grid_->set_visible_area(content_visible_area());
-		set_dirty();
-		return true;
-	}
-
-	return false;
-}
-
 void tlistbox::place(const tpoint& origin, const tpoint& size)
 {
 	// Inherited.
diff --git a/src/gui/widgets/listbox.hpp b/src/gui/widgets/listbox.hpp
index d151819ee43..2e0cb24361b 100644
--- a/src/gui/widgets/listbox.hpp
+++ b/src/gui/widgets/listbox.hpp
@@ -179,22 +179,6 @@ public:
 //		{ state_ = active ? ENABLED : DISABLED; }
 //
 
-	/**
-	 * Request to update the size of the content after changing the content.
-	 *
-	 * When a resize is required the container first can try to handle it
-	 * itself. If it can't honour the request the function will call @ref
-	 * twindow::invalidate_layout().
-	 *
-	 * @note Calling this function on a widget with size == (0, 0) results
-	 * false but doesn't call invalidate_layout, the engine expects to be in
-	 * build up phase with the layout already invalidated.
-	 *
-	 * @returns                      True if the resizing succeeded, false
-	 *                               otherwise.
-	 */
-	bool update_content_size();
-
 	/***** ***** ***** ***** inherited ***** ***** ****** *****/
 
 	/** Inherited from tscrollbar_container. */