diff --git a/src/script/script_gui.cpp b/src/script/script_gui.cpp
--- a/src/script/script_gui.cpp
+++ b/src/script/script_gui.cpp
@@ -696,7 +696,7 @@ struct ScriptDebugWindow : public Window
 	bool autoscroll;                                       ///< Whether automatically scrolling should be enabled or not.
 	bool show_break_box;                                   ///< Whether the break/debug box is visible.
 	static bool break_check_enabled;                       ///< Stop an AI when it prints a matching string
-	static char break_string[MAX_BREAK_STR_STRING_LENGTH]; ///< The string to match to the AI output
+	static std::string break_string;                       ///< The string to match to the AI output
 	QueryString break_editbox;                             ///< Break editbox
 	static StringFilter break_string_filter;               ///< Log filter for break.
 	static bool case_sensitive_break_check;                ///< Is the matching done case-sensitive
@@ -1022,7 +1022,7 @@ struct ScriptDebugWindow : public Window
 		if (wid != WID_SCRD_BREAK_STR_EDIT_BOX) return;
 
 		/* Save the current string to static member so it can be restored next time the window is opened. */
-		strecpy(this->break_string, this->break_editbox.text.buf, lastof(this->break_string));
+		this->break_string = this->break_editbox.text.buf;
 		break_string_filter.SetFilterTerm(this->break_string);
 	}
 
@@ -1098,7 +1098,7 @@ struct ScriptDebugWindow : public Window
 };
 
 CompanyID ScriptDebugWindow::script_debug_company = INVALID_COMPANY;
-char ScriptDebugWindow::break_string[MAX_BREAK_STR_STRING_LENGTH] = "";
+std::string ScriptDebugWindow::break_string;
 bool ScriptDebugWindow::break_check_enabled = true;
 bool ScriptDebugWindow::case_sensitive_break_check = false;
 StringFilter ScriptDebugWindow::break_string_filter(&ScriptDebugWindow::case_sensitive_break_check);
diff --git a/src/stringfilter.cpp b/src/stringfilter.cpp
--- a/src/stringfilter.cpp
+++ b/src/stringfilter.cpp
@@ -84,6 +84,15 @@ void StringFilter::SetFilterTerm(const c
 }
 
 /**
+ * Set the term to filter on.
+ * @param str Filter term
+ */
+void StringFilter::SetFilterTerm(const std::string &str)
+{
+	this->SetFilterTerm(str.c_str());
+}
+
+/**
  * Reset the matching state to process a new item.
  */
 void StringFilter::ResetState()
diff --git a/src/stringfilter_type.h b/src/stringfilter_type.h
--- a/src/stringfilter_type.h
+++ b/src/stringfilter_type.h
@@ -51,6 +51,7 @@ public:
 	~StringFilter() { free(this->filter_buffer); }
 
 	void SetFilterTerm(const char *str);
+	void SetFilterTerm(const std::string &str);
 
 	/**
 	 * Check whether any filter words were entered.