diff --git a/finance_tracker/web/app.py b/finance_tracker/web/app.py
index 8abbeca..ec2b9e5 100644
--- a/finance_tracker/web/app.py
+++ b/finance_tracker/web/app.py
@@ -13,6 +13,7 @@
 import html as _html
 import json
 import streamlit as st
+import streamlit.components.v1 as st_components
 import os
 from finance_tracker.web.db import get_session, get_db_path, get_engine
 from finance_tracker.web.navigation import build_pages
@@ -118,60 +119,71 @@ def render_db_manager():
 
             st.rerun()
 
-        # Animated arrow hinting at the sidebar toggle after 20 s of inactivity.
-        # st.html() (Streamlit ≥1.36) renders inline and executes <script> tags
-        # directly in the main window — no iframe, no window.parent needed.
-        # The full innerHTML is built in Python so translation is guaranteed.
-        # _sbShowing guards the poll so it only dismisses after the hint is visible,
-        # preventing the poll from firing sbVisited before the hint ever appears.
+        # Animated ↖ arrow hinting at the sidebar toggle after 20 s of inactivity.
+        #
+        # Architecture note: both st.html() and st.components.v1.html() render
+        # inside an iframe. Code in an iframe cannot reliably set long-lived timers
+        # because the iframe may be destroyed on Streamlit re-renders. The solution
+        # is to inject a <script> element into window.parent.document.head: inline
+        # scripts execute immediately and synchronously in the MAIN window context,
+        # so their timers survive re-renders. The iframe script runs once (guarded
+        # by window.parent._sbHintInit) and delegates everything else to the
+        # main-context script.
         _hint_inner = json.dumps(
             '<div class="_a">&#x2196;</div>'
             f'<div class="_t">{_html.escape(t("app.sidebar_hint"))}</div>'
         )
-        st.html(f"""<script>
+        # Plain Python string — no f-string, so { } are JS literals, no escaping.
+        _main_script = (
+            "(function(){"
+            "if(window._sbRunInit)return;"
+            "window._sbRunInit=true;"
+            "if(sessionStorage.getItem('sbVisited'))return;"
+            "var s=document.createElement('style');"
+            "s.textContent='@keyframes sb-bounce{0%,100%{transform:translate(0,0);opacity:1}"
+            "50%{transform:translate(-9px,-9px);opacity:.75}}"
+            "#_sb_hint{display:none;position:fixed;top:68px;left:44px;z-index:99999;"
+            "flex-direction:column;align-items:flex-start;gap:3px;pointer-events:none}"
+            "#_sb_hint ._a{font-size:22px;color:#0088ff;"
+            "animation:sb-bounce 1.1s ease-in-out infinite;line-height:1}"
+            "#_sb_hint ._t{background:#0088ff;color:#fff;padding:3px 9px;"
+            "border-radius:10px;font-size:11px;white-space:nowrap;"
+            "font-family:sans-serif;font-weight:600;"
+            "box-shadow:0 2px 6px rgba(0,136,255,.4)}';"
+            "document.head.appendChild(s);"
+            "var h=document.createElement('div');"
+            "h.id='_sb_hint';"
+            f"h.innerHTML={_hint_inner};"
+            "document.body.appendChild(h);"
+            "function closed(){"
+            "var b=document.querySelector('[data-testid=\"stSidebarCollapsedControl\"]');"
+            "return !!b&&getComputedStyle(b).display!=='none';}"
+            "function dismiss(){"
+            "sessionStorage.setItem('sbVisited','1');"
+            "window._sbShowing=false;"
+            "h.style.display='none';"
+            "if(window._sbTimer){clearTimeout(window._sbTimer);window._sbTimer=null;}"
+            "if(window._sbPoll){clearInterval(window._sbPoll);window._sbPoll=null;}}"
+            "window._sbPoll=setInterval(function(){"
+            "if(sessionStorage.getItem('sbVisited')){clearInterval(window._sbPoll);return;}"
+            "if(window._sbShowing&&!closed())dismiss();},400);"
+            "window._sbTimer=setTimeout(function(){"
+            "if(!sessionStorage.getItem('sbVisited')&&closed()){"
+            "h.style.display='flex';window._sbShowing=true;}},20000);"
+            "})()"
+        )
+        _main_script_json = json.dumps(_main_script)
+        st_components.html(f"""<script>
 (function(){{
-    if(window._sbHintInit)return;
-    window._sbHintInit=true;
-    if(sessionStorage.getItem('sbVisited'))return;
-    var s=document.createElement('style');
-    s.textContent='@keyframes sb-bounce{{0%,100%{{transform:translate(0,0);opacity:1}}'
-        +'50%{{transform:translate(-9px,-9px);opacity:.75}}}}'
-        +'#_sb_hint{{display:none;position:fixed;top:68px;left:44px;z-index:99999;'
-        +'flex-direction:column;align-items:flex-start;gap:3px;pointer-events:none}}'
-        +'#_sb_hint ._a{{font-size:22px;color:#0088ff;'
-        +'animation:sb-bounce 1.1s ease-in-out infinite;line-height:1}}'
-        +'#_sb_hint ._t{{background:#0088ff;color:#fff;padding:3px 9px;'
-        +'border-radius:10px;font-size:11px;white-space:nowrap;'
-        +'font-family:sans-serif;font-weight:600;'
-        +'box-shadow:0 2px 6px rgba(0,136,255,.4)}}';
-    document.head.appendChild(s);
-    var h=document.createElement('div');
-    h.id='_sb_hint';
-    h.innerHTML={_hint_inner};
-    document.body.appendChild(h);
-    function sidebarIsClosed(){{
-        var btn=document.querySelector('[data-testid="stSidebarCollapsedControl"]');
-        return !!btn&&getComputedStyle(btn).display!=='none';
-    }}
-    function dismiss(){{
-        sessionStorage.setItem('sbVisited','1');
-        window._sbShowing=false;
-        h.style.display='none';
-        if(window._sbTimer){{clearTimeout(window._sbTimer);window._sbTimer=null;}}
-        if(window._sbPoll){{clearInterval(window._sbPoll);window._sbPoll=null;}}
-    }}
-    window._sbPoll=setInterval(function(){{
-        if(sessionStorage.getItem('sbVisited')){{clearInterval(window._sbPoll);return;}}
-        if(window._sbShowing&&!sidebarIsClosed())dismiss();
-    }},400);
-    window._sbTimer=setTimeout(function(){{
-        if(!sessionStorage.getItem('sbVisited')&&sidebarIsClosed()){{
-            h.style.display='flex';
-            window._sbShowing=true;
-        }}
-    }},20000);
+    var p=window.parent;
+    if(!p||p._sbHintInit)return;
+    p._sbHintInit=true;
+    var ps=p.document.createElement('script');
+    ps.textContent={_main_script_json};
+    p.document.head.appendChild(ps);
+    ps.remove();
 }})();
-</script>""")
+</script>""", height=0)
 
         # Show documentation (needs no DB) so users aren't stranded on a blank page
         from finance_tracker.web.views.documentation import render as doc_render