diff --git a/apps/x/apps/renderer/src/App.tsx b/apps/x/apps/renderer/src/App.tsx
index b810af9b..e18c9d47 100644
--- a/apps/x/apps/renderer/src/App.tsx
+++ b/apps/x/apps/renderer/src/App.tsx
@@ -2748,6 +2748,7 @@ function App() {
     : null
   const isRightPaneContext = Boolean(selectedPath || isGraphOpen)
   const isRightPaneOnlyMode = isRightPaneContext && isChatSidebarOpen && isRightPaneMaximized
+  const shouldCollapseLeftPane = isRightPaneOnlyMode
   const openMarkdownTabs = React.useMemo(() => {
     const markdownTabs = fileTabs.filter(tab => tab.path.endsWith('.md'))
     if (selectedPath?.endsWith('.md')) {
@@ -2843,9 +2844,13 @@ function App() {
               backgroundTasks={backgroundTasks}
               selectedBackgroundTask={selectedBackgroundTask}
             />
-            {!isRightPaneOnlyMode && (
             <SidebarInset
-              className="overflow-hidden! min-h-0 min-w-0"
+              className={cn(
+                "overflow-hidden! min-h-0 min-w-0 transition-[max-width] duration-200 ease-linear",
+                shouldCollapseLeftPane && "pointer-events-none select-none"
+              )}
+              style={shouldCollapseLeftPane ? { maxWidth: 0 } : { maxWidth: '100%' }}
+              aria-hidden={shouldCollapseLeftPane}
               onMouseDownCapture={() => setActiveShortcutPane('left')}
               onFocusCapture={() => setActiveShortcutPane('left')}
             >
@@ -3136,7 +3141,6 @@ function App() {
               </FileCardProvider>
               )}
             </SidebarInset>
-            )}
 
             {/* Chat sidebar - shown when viewing files/graph */}
             {isRightPaneContext && (
diff --git a/apps/x/apps/renderer/src/components/chat-sidebar.tsx b/apps/x/apps/renderer/src/components/chat-sidebar.tsx
index 1e8610dd..05e498f7 100644
--- a/apps/x/apps/renderer/src/components/chat-sidebar.tsx
+++ b/apps/x/apps/renderer/src/components/chat-sidebar.tsx
@@ -154,6 +154,8 @@ export function ChatSidebar({
   const paneRef = useRef<HTMLDivElement>(null)
   const startXRef = useRef(0)
   const startWidthRef = useRef(0)
+  const prevIsMaximizedRef = useRef(isMaximized)
+  const justToggledMaximize = prevIsMaximizedRef.current !== isMaximized
 
   const getMaxAllowedWidth = useCallback(() => {
     if (typeof window === 'undefined') return MAX_WIDTH
@@ -183,6 +185,10 @@ export function ChatSidebar({
     setShowContent(false)
   }, [isOpen])
 
+  useEffect(() => {
+    prevIsMaximizedRef.current = isMaximized
+  }, [isMaximized])
+
   useEffect(() => {
     if (typeof window === 'undefined') return
     try {
@@ -343,7 +349,7 @@ export function ChatSidebar({
       onFocusCapture={onActivate}
       className={cn(
         'relative flex min-w-0 flex-col overflow-hidden border-l border-border bg-background',
-        !isResizing && 'transition-[width] duration-200 ease-linear'
+        !isResizing && !justToggledMaximize && 'transition-[width] duration-200 ease-linear'
       )}
       style={paneStyle}
     >