From 587b113c84e06ccf1a1d5cf51609b523e7d65d29 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Wed, 11 Nov 2020 15:03:45 +0530
Subject: [PATCH] Viewer: Fix previous/next buttons iterating over removed
 bookmarks

---
 src/calibre/gui2/viewer/bookmarks.py | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/src/calibre/gui2/viewer/bookmarks.py b/src/calibre/gui2/viewer/bookmarks.py
index a159e11d5d..8868d77ad5 100644
--- a/src/calibre/gui2/viewer/bookmarks.py
+++ b/src/calibre/gui2/viewer/bookmarks.py
@@ -51,11 +51,17 @@ class BookmarksList(QListWidget):
         return QListWidget.keyPressEvent(self, ev)
 
     def activate_related_bookmark(self, delta=1):
-        if self.count() > 0:
-            row = self.currentRow()
-            nrow = (row + delta + self.count()) % self.count()
-            self.setCurrentRow(nrow)
-            self.bookmark_activated.emit(self.currentItem())
+        if not self.count():
+            return
+        items = [self.item(r) for r in range(self.count())]
+        row = self.currentRow()
+        current_item = items[row]
+        items = [i for i in items if not i.isHidden()]
+        count = len(items)
+        row = items.index(current_item)
+        nrow = (row + delta + count) % count
+        self.setCurrentItem(items[nrow])
+        self.bookmark_activated.emit(self.currentItem())
 
     def next_bookmark(self):
         self.activate_related_bookmark()