From 202528eda965cc2105349c0583775af33353bfc8 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Thu, 11 Aug 2016 19:56:34 +0530
Subject: [PATCH] E-book viewer: Fix books that set side margins on body using
 percentages not working correctly. Fixes #1608458 [Private
 bug](https://bugs.launchpad.net/calibre/+bug/1608458)

---
 src/calibre/gui2/viewer/documentview.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/calibre/gui2/viewer/documentview.py b/src/calibre/gui2/viewer/documentview.py
index 6566faecbc..415211162e 100644
--- a/src/calibre/gui2/viewer/documentview.py
+++ b/src/calibre/gui2/viewer/documentview.py
@@ -921,6 +921,9 @@ class DocumentView(QWebView):  # {{{
     def load_path(self, path, pos=0.0):
         self.initial_pos = pos
         self.last_loaded_path = path
+        # This is needed otherwise percentage margins on body are not correctly
+        # evaluated in read_document_margins() in paged mode.
+        self.document.setPreferredContentsSize(QSize())
 
         def callback(lu):
             self.loading_url = lu