diff --git a/demo/markdownlint-browser.js b/demo/markdownlint-browser.js
index 0c668519..b8d4f6ab 100644
--- a/demo/markdownlint-browser.js
+++ b/demo/markdownlint-browser.js
@@ -307,23 +307,6 @@ module.exports.unorderedListStyleFor = function unorderedListStyleFor(token) {
  * @returns {void}
  */
 
-/**
- * Calls the provided function for each matching token.
- *
- * @param {Object} params RuleParams instance.
- * @param {string} type Token type identifier.
- * @param {TokenCallback} handler Callback function.
- * @returns {void}
- */
-function filterTokens(params, type, handler) {
-  for (const token of params.parsers.markdownit.tokens) {
-    if (token.type === type) {
-      handler(token);
-    }
-  }
-}
-module.exports.filterTokens = filterTokens;
-
 // Returns (nested) lists as a flat array (in order)
 module.exports.flattenLists = function flattenLists(tokens) {
   const flattenedLists = [];
diff --git a/helpers/helpers.js b/helpers/helpers.js
index 0503d253..5a00db37 100644
--- a/helpers/helpers.js
+++ b/helpers/helpers.js
@@ -295,23 +295,6 @@ module.exports.unorderedListStyleFor = function unorderedListStyleFor(token) {
  * @returns {void}
  */
 
-/**
- * Calls the provided function for each matching token.
- *
- * @param {Object} params RuleParams instance.
- * @param {string} type Token type identifier.
- * @param {TokenCallback} handler Callback function.
- * @returns {void}
- */
-function filterTokens(params, type, handler) {
-  for (const token of params.parsers.markdownit.tokens) {
-    if (token.type === type) {
-      handler(token);
-    }
-  }
-}
-module.exports.filterTokens = filterTokens;
-
 // Returns (nested) lists as a flat array (in order)
 module.exports.flattenLists = function flattenLists(tokens) {
   const flattenedLists = [];
diff --git a/test/rules/any-blockquote.js b/test/rules/any-blockquote.js
index 59372328..7cd27e7a 100644
--- a/test/rules/any-blockquote.js
+++ b/test/rules/any-blockquote.js
@@ -2,11 +2,6 @@
 
 "use strict";
 
-const { filterTokens } = require("../../helpers");
-
-/** @typedef {import("../../lib/markdownlint").MarkdownItToken} MarkdownItToken */
-/** @typedef {(MarkdownItToken) => void} FilterTokensCallback */
-
 /** @type import("../../lib/markdownlint").Rule */
 module.exports = {
   "names": [ "any-blockquote" ],
@@ -18,18 +13,15 @@ module.exports = {
   "tags": [ "test" ],
   "parser": "markdownit",
   "function": (params, onError) => {
-    filterTokens(
-      params,
-      "blockquote_open",
-      /** @type FilterTokensCallback */
-      (blockquote) => {
-        const lines = blockquote.map[1] - blockquote.map[0];
-        onError({
-          "lineNumber": blockquote.lineNumber,
-          "detail": "Blockquote spans " + lines + " line(s).",
-          "context": blockquote.line.substr(0, 7)
-        });
-      }
-    );
+    const blockquotes = params.parsers.markdownit.tokens.
+      filter((token => token.type === "blockquote_open"));
+    for (const blockquote of blockquotes) {
+      const lines = blockquote.map[1] - blockquote.map[0];
+      onError({
+        "lineNumber": blockquote.lineNumber,
+        "detail": "Blockquote spans " + lines + " line(s).",
+        "context": blockquote.line.substr(0, 7)
+      });
+    }
   }
 };
diff --git a/test/rules/lint-javascript.js b/test/rules/lint-javascript.js
index c2d5380c..807d4cc4 100644
--- a/test/rules/lint-javascript.js
+++ b/test/rules/lint-javascript.js
@@ -3,7 +3,6 @@
 "use strict";
 
 const js = require("@eslint/js");
-const { filterTokens } = require("../../helpers");
 const eslint = require("eslint");
 const linter = new eslint.Linter();
 const languageJavaScript = /js|javascript/i;
@@ -15,7 +14,9 @@ module.exports = {
   "tags": [ "test", "lint", "javascript" ],
   "parser": "markdownit",
   "function": (params, onError) => {
-    filterTokens(params, "fence", (fence) => {
+    const fences = params.parsers.markdownit.tokens.
+      filter((token => token.type === "fence"));
+    for (const fence of fences) {
       if (languageJavaScript.test(fence.info)) {
         const results = linter.verify(fence.content, js.configs.recommended);
         for (const result of results) {
@@ -27,9 +28,9 @@ module.exports = {
           });
         }
       }
-    });
-    // Unsupported:
-    //   filterTokens("code_block"), language unknown
-    //   filterTokens("code_inline"), too brief
+    }
+    // Unsupported by this sample:
+    //   "code_block": language unknown
+    //   "code_inline": too brief
   }
 };
diff --git a/test/rules/validate-json.js b/test/rules/validate-json.js
index b0feac8b..ab669f7c 100644
--- a/test/rules/validate-json.js
+++ b/test/rules/validate-json.js
@@ -2,7 +2,6 @@
 
 "use strict";
 
-const { filterTokens } = require("../../helpers");
 const { parse, printParseErrorCode } = require("jsonc-parser");
 
 /** @type import("../../lib/markdownlint").Rule */
@@ -13,7 +12,9 @@ module.exports = {
   "parser": "markdownit",
   "asynchronous": true,
   "function": (params, onError) => {
-    filterTokens(params, "fence", (fence) => {
+    const fences = params.parsers.markdownit.tokens.
+      filter((token => token.type === "fence"));
+    for (const fence of fences) {
       if (/jsonc?/i.test(fence.info)) {
         const errors = [];
         parse(fence.content, errors);
@@ -28,6 +29,6 @@ module.exports = {
           });
         }
       }
-    });
+    }
   }
 };