From f0821878445b17b853e3b5c0e1e8d31f071857c9 Mon Sep 17 00:00:00 2001
From: Sorin Davidoi <sorin.davidoi@gmail.com>
Date: Thu, 25 Jan 2018 11:44:22 +0100
Subject: [PATCH] fix(theme/book): Use passive listeners for touchstart,
 touchmove (#575)

---
 src/theme/book.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/theme/book.js b/src/theme/book.js
index f686af44..2fb48eff 100644
--- a/src/theme/book.js
+++ b/src/theme/book.js
@@ -422,7 +422,7 @@ function playpen_text(playpen) {
             x: e.touches[0].clientX,
             time: Date.now()
         };
-    });
+    }, { passive: true });
 
     document.addEventListener('touchmove', function (e) {
         if (!firstContact)
@@ -440,7 +440,7 @@ function playpen_text(playpen) {
 
             firstContact = null;
         }
-    });
+    }, { passive: true });
 
     // Scroll sidebar to current active section
     var activeSection = sidebar.querySelector(".active");