Popup toggle for collapsing long user messages

extension/manifest.chrome.json

@@ -1,7 +1,7 @@
 {
   "manifest_version": 3,
   "name": "LightSession Pro for ChatGPT",
-  "version": "1.6.3",
+  "version": "1.7.0",
   "description": "Keep ChatGPT fast by keeping only the last N messages in the DOM. Local-only.",
   "icons": {
     "16": "icons/icon-16.png",

extension/manifest.firefox.json

@@ -1,7 +1,7 @@
 {
   "manifest_version": 3,
   "name": "LightSession Pro for ChatGPT",
-  "version": "1.6.3",
+  "version": "1.7.0",
   "description": "Keep ChatGPT fast by keeping only the last N messages in the DOM. Local-only.",
   "icons": {
     "16": "icons/icon-16.png",

extension/popup/popup.html

@@ -86,6 +86,27 @@ <h1>LightSession Pro</h1>
             </div>
           </label>
 
+          <!-- Collapse long user messages -->
+          <label class="ls-checkbox-row">
+            <div class="ls-checkbox-wrapper">
+              <input
+                type="checkbox"
+                id="collapseLongUserMessagesCheckbox"
+                class="ls-checkbox-input"
+                aria-label="Collapse long user messages"
+              >
+              <div class="ls-checkbox-box">
+                <svg class="ls-checkbox-check" viewBox="0 0 12 12" fill="none">
+                  <path d="M2 6l3 3 5-6" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"/>
+                </svg>
+              </div>
+            </div>
+            <div class="ls-checkbox-label-group">
+              <span class="ls-checkbox-label">Collapse long user messages</span>
+              <span class="ls-checkbox-description">Reduce lag in long chats</span>
+            </div>
+          </label>
+
         </div>
       </section>
 

extension/src/content/content.ts

@@ -21,6 +21,7 @@ import {
   setStatusBarVisibility,
 } from './status-bar';
 import { isEmptyChatView } from './chat-view';
+import { installUserCollapse, type UserCollapseController } from './user-collapse';
 
 
 // ============================================================================
@@ -57,6 +58,7 @@ let proxyReady = false;
 let emptyChatState = false;
 let emptyChatCheckTimer: number | null = null;
 let emptyChatObserver: MutationObserver | null = null;
+let userCollapse: UserCollapseController | null = null;
 
 // ============================================================================
 // Page Script Communication
@@ -171,6 +173,18 @@ function applySettings(settings: LsSettings): void {
   // Apply Ultra Lean CSS mode (works independently of trimmer)
   setUltraLeanMode(settings.ultraLean);
 
+  // Collapse long user messages (presentation-only; local DOM feature)
+  const shouldCollapseLongUserMessages = settings.enabled && settings.collapseLongUserMessages;
+  if (shouldCollapseLongUserMessages) {
+    if (!userCollapse) {
+      userCollapse = installUserCollapse();
+    }
+    userCollapse.enable();
+  } else if (userCollapse) {
+    userCollapse.teardown();
+    userCollapse = null;
+  }
+
   logDebug('Settings applied:', settings);
 }