diff --git a/src/linkgraph/linkgraph_gui.cpp b/src/linkgraph/linkgraph_gui.cpp
--- a/src/linkgraph/linkgraph_gui.cpp
+++ b/src/linkgraph/linkgraph_gui.cpp
@@ -454,54 +454,54 @@ void LinkGraphOverlay::SetCompanyMask(Co
 }
 
 /** Make a number of rows with buttons for each company for the linkgraph legend window. */
-NWidgetBase *MakeCompanyButtonRowsLinkGraphGUI()
+std::unique_ptr<NWidgetBase> MakeCompanyButtonRowsLinkGraphGUI()
 {
 	return MakeCompanyButtonRows(WID_LGL_COMPANY_FIRST, WID_LGL_COMPANY_LAST, COLOUR_GREY, 3, STR_NULL);
 }
 
-NWidgetBase *MakeSaturationLegendLinkGraphGUI()
+std::unique_ptr<NWidgetBase> MakeSaturationLegendLinkGraphGUI()
 {
-	NWidgetVertical *panel = new NWidgetVertical(NC_EQUALSIZE);
+	auto panel = std::make_unique<NWidgetVertical>(NC_EQUALSIZE);
 	for (uint i = 0; i < lengthof(LinkGraphOverlay::LINK_COLOURS[0]); ++i) {
-		NWidgetBackground * wid = new NWidgetBackground(WWT_PANEL, COLOUR_DARK_GREEN, i + WID_LGL_SATURATION_FIRST);
+		auto wid = std::make_unique<NWidgetBackground>(WWT_PANEL, COLOUR_DARK_GREEN, i + WID_LGL_SATURATION_FIRST);
 		wid->SetMinimalSize(50, 0);
 		wid->SetMinimalTextLines(1, 0, FS_SMALL);
 		wid->SetFill(1, 1);
 		wid->SetResize(0, 0);
-		panel->Add(wid);
+		panel->Add(std::move(wid));
 	}
 	return panel;
 }
 
-NWidgetBase *MakeCargoesLegendLinkGraphGUI()
+std::unique_ptr<NWidgetBase> MakeCargoesLegendLinkGraphGUI()
 {
 	uint num_cargo = static_cast<uint>(_sorted_cargo_specs.size());
 	static const uint ENTRIES_PER_COL = 5;
-	NWidgetHorizontal *panel = new NWidgetHorizontal(NC_EQUALSIZE);
-	NWidgetVertical *col = nullptr;
+	auto panel = std::make_unique<NWidgetHorizontal>(NC_EQUALSIZE);
+	std::unique_ptr<NWidgetVertical> col = nullptr;
 
 	for (uint i = 0; i < num_cargo; ++i) {
 		if (i % ENTRIES_PER_COL == 0) {
-			if (col != nullptr) panel->Add(col);
-			col = new NWidgetVertical(NC_EQUALSIZE);
+			if (col != nullptr) panel->Add(std::move(col));
+			col = std::make_unique<NWidgetVertical>(NC_EQUALSIZE);
 		}
-		NWidgetBackground * wid = new NWidgetBackground(WWT_PANEL, COLOUR_GREY, i + WID_LGL_CARGO_FIRST);
+		auto wid = std::make_unique<NWidgetBackground>(WWT_PANEL, COLOUR_GREY, i + WID_LGL_CARGO_FIRST);
 		wid->SetMinimalSize(25, 0);
 		wid->SetMinimalTextLines(1, 0, FS_SMALL);
 		wid->SetFill(1, 1);
 		wid->SetResize(0, 0);
-		col->Add(wid);
+		col->Add(std::move(wid));
 	}
 	/* Fill up last row */
 	for (uint i = num_cargo; i < Ceil(num_cargo, ENTRIES_PER_COL); ++i) {
-		NWidgetSpacer *spc = new NWidgetSpacer(25, 0);
+		auto spc = std::make_unique<NWidgetSpacer>(25, 0);
 		spc->SetMinimalTextLines(1, 0, FS_SMALL);
 		spc->SetFill(1, 1);
 		spc->SetResize(0, 0);
-		col->Add(spc);
+		col->Add(std::move(spc));
 	}
 	/* If there are no cargo specs defined, then col won't have been created so don't add it. */
-	if (col != nullptr) panel->Add(col);
+	if (col != nullptr) panel->Add(std::move(col));
 	return panel;
 }