diff --git a/src/core/Parser.ts b/src/core/Parser.ts
index 673d7ecf..6ad4c946 100644
--- a/src/core/Parser.ts
+++ b/src/core/Parser.ts
@@ -76,7 +76,7 @@ export class Parser {
   }
 
   read(node: Pos) {
-    return this.substring(node.pos, node.endPos);
+    return this.data.slice(node.pos, node.endPos);
   }
 
   reset() {
@@ -252,10 +252,6 @@ export class Parser {
     this.pos = this.maxPos + 1;
   }
 
-  substring(pos: number, endPos?: number) {
-    return this.data.substring(pos, endPos);
-  }
-
   /**
    * This is called to determine if a tag is an "open only tag". Open only tags such as <img>
    * are immediately closed.