diff --git a/plugins/chat/assets/javascripts/discourse/lib/simple-category-hash-mention-transform.js b/plugins/chat/assets/javascripts/discourse/lib/simple-category-hash-mention-transform.js
deleted file mode 100644
index 37f85fb2c51..00000000000
--- a/plugins/chat/assets/javascripts/discourse/lib/simple-category-hash-mention-transform.js
+++ /dev/null
@@ -1,43 +0,0 @@
-import getURL from "discourse-common/lib/get-url";
-
-const domParser = new DOMParser();
-
-export default function transform(cooked, categories) {
-  let html = domParser.parseFromString(cooked, "text/html");
-  transformMentions(html);
-  transformCategoryTagHashes(html, categories);
-  return html.body.innerHTML;
-}
-
-function transformMentions(html) {
-  (html.querySelectorAll("span.mention") || []).forEach((mentionSpan) => {
-    let mentionLink = document.createElement("a");
-    let mentionText = document.createTextNode(mentionSpan.innerText);
-    mentionLink.classList.add("mention");
-    mentionLink.appendChild(mentionText);
-    mentionLink.href = getURL(`/u/${mentionSpan.innerText.substring(1)}`);
-    mentionSpan.parentNode.replaceChild(mentionLink, mentionSpan);
-  });
-}
-
-function transformCategoryTagHashes(html, categories) {
-  (html.querySelectorAll("span.hashtag") || []).forEach((hashSpan) => {
-    const categoryTagName = hashSpan.innerText.substring(1);
-    const matchingCategory = categories.find(
-      (category) =>
-        category.name.toLowerCase() === categoryTagName.toLowerCase()
-    );
-    const href = getURL(
-      matchingCategory
-        ? `/c/${matchingCategory.name}/${matchingCategory.id}`
-        : `/tag/${categoryTagName}`
-    );
-
-    let hashLink = document.createElement("a");
-    let hashText = document.createTextNode(hashSpan.innerText);
-    hashLink.classList.add("hashtag");
-    hashLink.appendChild(hashText);
-    hashLink.href = href;
-    hashSpan.parentNode.replaceChild(hashLink, hashSpan);
-  });
-}
diff --git a/plugins/chat/assets/javascripts/discourse/models/chat-message.js b/plugins/chat/assets/javascripts/discourse/models/chat-message.js
index 1cc2f2598fe..5c913750c19 100644
--- a/plugins/chat/assets/javascripts/discourse/models/chat-message.js
+++ b/plugins/chat/assets/javascripts/discourse/models/chat-message.js
@@ -5,7 +5,6 @@ import ChatMessageReaction from "discourse/plugins/chat/discourse/models/chat-me
 import Bookmark from "discourse/models/bookmark";
 import I18n from "I18n";
 import { generateCookFunction } from "discourse/lib/text";
-import simpleCategoryHashMentionTransform from "discourse/plugins/chat/discourse/lib/simple-category-hash-mention-transform";
 import { getOwner } from "discourse-common/lib/get-owner";
 import discourseLater from "discourse-common/lib/later";
 
@@ -192,10 +191,7 @@ export default class ChatMessage {
     } else {
       const cookFunction = await generateCookFunction(markdownOptions);
       ChatMessage.cookFunction = (raw) => {
-        return simpleCategoryHashMentionTransform(
-          cookFunction(raw),
-          site.categories
-        );
+        return cookFunction(raw);
       };
 
       this.cooked = ChatMessage.cookFunction(this.message);