Merge branch 'master' into jgrpp

# Conflicts:
#	src/3rdparty/fmt/core.h
#	src/command_type.h
#	src/console_cmds.cpp
#	src/core/overflowsafe_type.hpp
#	src/landscape.cpp
#	src/network/network.cpp
#	src/newgrf_object.h
#	src/object_cmd.cpp
#	src/order_gui.cpp
#	src/saveload/vehicle_sl.cpp
#	src/script/api/script_industrytype.cpp
#	src/script/api/script_object.hpp
#	src/script/api/script_town.cpp
#	src/table/object_land.h
#	src/timetable_cmd.cpp
#	src/tree_cmd.cpp
#	src/vehicle_gui.cpp
#	src/window.cpp

src/order_cmd.cpp

@@ -1778,6 +1778,7 @@ CommandCost CmdModifyOrder(TileIndex tile, DoCommandFlag flags, uint32 p1, uint3
 	if (sel_ord >= v->GetNumOrders()) return CMD_ERROR;
 
 	Order *order = v->GetOrder(sel_ord);
+	assert(order != nullptr);
 	switch (order->GetType()) {
 		case OT_GOTO_STATION:
 			if (mof != MOF_NON_STOP && mof != MOF_STOP_LOCATION && mof != MOF_UNLOAD && mof != MOF_LOAD && mof != MOF_CARGO_TYPE_UNLOAD && mof != MOF_CARGO_TYPE_LOAD && mof != MOF_RV_TRAVEL_DIR) return CMD_ERROR;