Added detection for broken/deleted bookmark links, can expand on this to automatically delete broken links, but for now it just hides the icon.

public/script.js

@@ -55,6 +55,7 @@ import {
     renameGroupChat,
     importGroupChat,
     getGroupBlock,
+    getGroupChatNames,
 } from "./scripts/group-chats.js";
 
 import {
@@ -1604,8 +1605,17 @@ function addOneMessage(mes, { type = "normal", insertAfter = null, scroll = true
         mes.is_user,
     );
     const bias = messageFormatting(mes.extra?.bias ?? "");
-    const bookmarkLink = mes?.extra?.bookmark_link ?? '';
+    let bookmarkLink = mes?.extra?.bookmark_link ?? '';
+    // Verify bookmarked chat still exists
+    if (bookmarkLink !== '' ) {
+        let chat_names = selected_group
+            ? getGroupChatNames(selected_group)
+            : Object.values(getPastCharacterChats()).map(({file_name}) => file_name);
 
+        if (!chat_names.includes(bookmarkLink)) {
+            bookmarkLink = ''
+        }
+    }
     let params = {
         mesId: count_view_mes,
         characterName: characterName,

public/scripts/group-chats.js

@@ -80,6 +80,7 @@ export {
     regenerateGroup,
     resetSelectedGroup,
     select_group_chats,
+    getGroupChatNames,
 }
 
 let is_group_generating = false; // Group generation flag
@@ -405,6 +406,19 @@ function getGroupAvatar(group) {
     return groupAvatar;
 }
 
+function getGroupChatNames(groupId) {
+    const group = groups.find(x => x.id === groupId);
+
+    if (!group) {
+        return [];
+    }
+
+    const names = [];
+    for (const chatId of group.chats) {
+        names.push(chatId);
+    }
+    return names;
+}
 
 async function generateGroupWrapper(by_auto_mode, type = null, params = {}) {
     if (online_status === "no_connection") {