From 12d701cb84b3d9f8ca385ccc4df0f2dc10aac6ae Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marek=20Jasi=C5=84ski?= <jasins.marek@gmail.com>
Date: Fri, 5 Jun 2026 20:00:31 +0200
Subject: [PATCH] fix(mobile-ux): guard ScrollToTopAsync JS interop to prevent
 prerendering runtime error

---
 .../Components/Organisms/ReaderCanvas.razor            | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/src/NexusReader.UI.Shared/Components/Organisms/ReaderCanvas.razor b/src/NexusReader.UI.Shared/Components/Organisms/ReaderCanvas.razor
index b13e133..9467195 100644
--- a/src/NexusReader.UI.Shared/Components/Organisms/ReaderCanvas.razor
+++ b/src/NexusReader.UI.Shared/Components/Organisms/ReaderCanvas.razor
@@ -432,8 +432,16 @@
     {
         try
         {
+            // Ensure the JS module is loaded and the component is fully rendered before invoking interop.
+            if (!_isJsInitialized)
+            {
+                await InitViewportDetectionAsync();
+            }
             var module = await EnsureViewportModuleAsync();
-            await module.InvokeVoidAsync("scrollToTop", ".reader-canvas");
+            if (module != null)
+            {
+                await module.InvokeVoidAsync("scrollToTop", ".reader-canvas");
+            }
         }
         catch (Exception ex)
         {