diff --git a/src/signs_gui.cpp b/src/signs_gui.cpp
--- a/src/signs_gui.cpp
+++ b/src/signs_gui.cpp
@@ -47,7 +47,7 @@ struct SignList {
 
 	StringFilter string_filter;                                       ///< The match string to be used when the GUIList is (re)-sorted.
 	static bool match_case;                                           ///< Should case sensitive matching be used?
-	static char default_name[64];                                     ///< Default sign name, used if Sign::name is nullptr.
+	static std::string default_name;                                  ///< Default sign name, used if Sign::name is nullptr.
 
 	/**
 	 * Creates a SignList with filtering disabled by default.
@@ -79,10 +79,10 @@ struct SignList {
 		 * a lot of them. Therefore a worthwhile performance gain can be made by
 		 * directly comparing Sign::name instead of going through the string
 		 * system for each comparison. */
-		const char *a_name = a->name.empty() ? SignList::default_name : a->name.c_str();
-		const char *b_name = b->name.empty() ? SignList::default_name : b->name.c_str();
+		const std::string &a_name = a->name.empty() ? SignList::default_name : a->name;
+		const std::string &b_name = b->name.empty() ? SignList::default_name : b->name;
 
-		int r = strnatcmp(a_name, b_name); // Sort by name (natural sorting).
+		int r = StrNaturalCompare(a_name, b_name); // Sort by name (natural sorting).
 
 		return r != 0 ? r < 0 : (a->index < b->index);
 	}
@@ -96,10 +96,10 @@ struct SignList {
 	static bool CDECL SignNameFilter(const Sign * const *a, StringFilter &filter)
 	{
 		/* Same performance benefit as above for sorting. */
-		const char *a_name = (*a)->name.empty() ? SignList::default_name : (*a)->name.c_str();
+		const std::string &a_name = (*a)->name.empty() ? SignList::default_name : (*a)->name;
 
 		filter.ResetState();
-		filter.AddLine(a_name);
+		filter.AddLine(a_name.c_str());
 		return filter.GetState();
 	}
 
@@ -130,7 +130,7 @@ struct SignList {
 };
 
 bool SignList::match_case = false;
-char SignList::default_name[64];
+std::string SignList::default_name;
 
 /** Enum referring to the Hotkeys in the sign list window */
 enum SignListHotkeys {
@@ -165,7 +165,7 @@ struct SignListWindow : Window, SignList
 	void OnInit() override
 	{
 		/* Default sign name, used if Sign::name is nullptr. */
-		GetString(SignList::default_name, STR_DEFAULT_SIGN_NAME, lastof(SignList::default_name));
+		SignList::default_name = GetString(STR_DEFAULT_SIGN_NAME);
 		this->signs.ForceResort();
 		this->SortSignsList();
 		this->SetDirty();