Looks like this was added to 18.08 (then master) before d75ec381

and was missed.

This is no longer needed.

src/plugins/accounting_storage/mysql/as_mysql_job.c

@@ -963,12 +963,9 @@ extern int as_mysql_job_complete(mysql_conn_t *mysql_conn,
 		xstrfmtcat(query, ", admin_comment='%s'",
 			   job_ptr->admin_comment);
 
-	if (job_ptr->system_comment) {
-		char *comment = slurm_add_slash_to_quotes(
-			job_ptr->system_comment);
-		xstrfmtcat(query, ", system_comment='%s'", comment);
-		xfree(comment);
-	}
+	if (job_ptr->system_comment)
+		xstrfmtcat(query, ", system_comment='%s'",
+			   job_ptr->system_comment);
 
 	exit_code = job_ptr->exit_code;
 	if (exit_code == 1) {