diff --git a/backend/server/dist/index.js b/backend/server/dist/index.js
index 5ff97cb..2134505 100644
--- a/backend/server/dist/index.js
+++ b/backend/server/dist/index.js
@@ -57,7 +57,8 @@ io.use((socket, next) => __awaiter(void 0, void 0, void 0, function* () {
         return;
     }
     const sandbox = dbUserJSON.sandbox.find((s) => s.id === sandboxId);
-    if (!sandbox) {
+    const sharedSandboxes = dbUserJSON.usersToSandboxes.find((uts) => uts.sandboxId === sandboxId);
+    if (!sandbox && !sharedSandboxes) {
         console.log("Invalid credentials.");
         next(new Error("Invalid credentials."));
         return;
diff --git a/backend/server/src/index.ts b/backend/server/src/index.ts
index 835f27b..039a261 100644
--- a/backend/server/src/index.ts
+++ b/backend/server/src/index.ts
@@ -63,8 +63,11 @@ io.use(async (socket, next) => {
   }
 
   const sandbox = dbUserJSON.sandbox.find((s) => s.id === sandboxId)
+  const sharedSandboxes = dbUserJSON.usersToSandboxes.find(
+    (uts) => uts.sandboxId === sandboxId
+  )
 
-  if (!sandbox) {
+  if (!sandbox && !sharedSandboxes) {
     console.log("Invalid credentials.")
     next(new Error("Invalid credentials."))
     return
diff --git a/frontend/app/globals.css b/frontend/app/globals.css
index 5d2838d..abbbb13 100644
--- a/frontend/app/globals.css
+++ b/frontend/app/globals.css
@@ -106,4 +106,39 @@
   padding: 2px 4px;
   border-radius: 4px;
   margin-left: 56px;
+}
+
+.yRemoteSelection {
+  opacity: 0.5;
+  background-color: var(--user-color);
+  margin-right: -1px;
+}
+
+/* Cursor caret */
+.yRemoteSelectionHead {
+  position: absolute;
+  box-sizing: border-box;
+  height: 100%;
+  border-left: 2px solid var(--user-color);
+}
+
+/* Cursor name */
+.yRemoteSelectionHead::after {
+  position: absolute;
+  top: -1.4em;
+  left: -2px;
+  padding: 2px 6px;
+  background: var(--user-color);
+  color: #fff;
+  border: 0;
+  border-radius: 6px;
+  border-bottom-left-radius: 0;
+  line-height: normal;
+  white-space: nowrap;
+  font-size: 14px;
+  font-style: normal;
+  font-weight: 600;
+  pointer-events: none;
+  user-select: none;
+  z-index: 1000;
 }
\ No newline at end of file
diff --git a/frontend/components/editor/index.tsx b/frontend/components/editor/index.tsx
index 72f5fad..5f51dd4 100644
--- a/frontend/components/editor/index.tsx
+++ b/frontend/components/editor/index.tsx
@@ -42,7 +42,6 @@ import { TFile, TFileData, TFolder, TTab } from "./sidebar/types"
 import { User } from "@/lib/types"
 import { processFileType, validateName } from "@/lib/utils"
 import { Cursors } from "./live/cursors"
-import { Avatars } from "./live/avatars"
 
 export default function CodeEditor({
   userData,
@@ -271,26 +270,31 @@ export default function CodeEditor({
   })
 
   useEffect(() => {
-    if (!editorRef.current) return
+    let yProvider: any
+    let yDoc: Y.Doc
+    let binding: MonacoBinding
 
-    const yDoc = new Y.Doc()
-    const yText = yDoc.getText("monaco")
-    const yProvider: any = new LiveblocksProvider(room, yDoc)
-    setProvider(yProvider)
+    if (editorRef.current) {
+      yDoc = new Y.Doc()
+      const yText = yDoc.getText("monaco")
+      yProvider = new LiveblocksProvider(room, yDoc)
+      setProvider(yProvider)
 
-    const binding = new MonacoBinding(
-      yText,
-      editorRef.current.getModel() as monaco.editor.ITextModel,
-      new Set([editorRef.current]),
-      yProvider.awareness as Awareness
-    )
+      // Attach Yjs to Monaco
+      binding = new MonacoBinding(
+        yText,
+        editorRef.current.getModel() as monaco.editor.ITextModel,
+        new Set([editorRef.current]),
+        yProvider.awareness as Awareness
+      )
+    }
 
     return () => {
-      yDoc.destroy()
-      yProvider.destroy()
-      binding.destroy()
+      yDoc?.destroy()
+      yProvider?.destroy()
+      binding?.destroy()
     }
-  }, [editorRef, room])
+  }, [editorRef.current, room])
 
   // connection/disconnection effect + resizeobserver
   useEffect(() => {
@@ -490,7 +494,6 @@ export default function CodeEditor({
                 {tab.name}
               </Tab>
             ))}
-            <Avatars />
           </div>
           <div
             ref={editorContainerRef}
diff --git a/frontend/components/editor/live/cursors.tsx b/frontend/components/editor/live/cursors.tsx
index c86dd47..b1269e3 100644
--- a/frontend/components/editor/live/cursors.tsx
+++ b/frontend/components/editor/live/cursors.tsx
@@ -19,6 +19,7 @@ export function Cursors({ yProvider }: { yProvider: TypedLiveblocksProvider }) {
 
     // On changes, update `awarenessUsers`
     function setUsers() {
+      console.log("SET USERS")
       setAwarenessUsers(
         Array.from(yProvider.awareness.getStates()) as AwarenessList
       )
diff --git a/frontend/components/editor/navbar/index.tsx b/frontend/components/editor/navbar/index.tsx
index ae45487..a7cc9d2 100644
--- a/frontend/components/editor/navbar/index.tsx
+++ b/frontend/components/editor/navbar/index.tsx
@@ -10,6 +10,7 @@ import { Button } from "@/components/ui/button"
 import { useState } from "react"
 import EditSandboxModal from "./edit"
 import ShareSandboxModal from "./share"
+import { Avatars } from "../live/avatars"
 
 export default function Navbar({
   userData,
@@ -58,6 +59,8 @@ export default function Navbar({
           </div>
         </div>
         <div className="flex items-center space-x-4">
+          <Avatars />
+
           <Button variant="outline" onClick={() => setIsShareOpen(true)}>
             <Users className="w-4 h-4 mr-2" />
             Share