From f9a16901750a9f31f498c2b545960a4754697e79 Mon Sep 17 00:00:00 2001
From: Vincent Vanwaelscappel <vincent@cubedesigners.com>
Date: Thu, 1 Oct 2020 12:50:06 +0200
Subject: [PATCH] fix #2863 @1

---
 js/libs/fluidbook/fluidbook.loader.js          |  2 +-
 js/libs/fluidbook/fluidbook.pagetransitions.js |  4 ++--
 js/libs/fluidbook/fluidbook.support.js         | 16 ++++++++++++++++
 3 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/js/libs/fluidbook/fluidbook.loader.js b/js/libs/fluidbook/fluidbook.loader.js
index 323ed20e..148cdb4b 100644
--- a/js/libs/fluidbook/fluidbook.loader.js
+++ b/js/libs/fluidbook/fluidbook.loader.js
@@ -418,7 +418,7 @@ FluidbookLoader.prototype = {
     },
 
     _loadTexture: function (page, callback) {
-        if (page <= 0 || page > this.fluidbook.settings.pages) {
+        if (!this.fluidbook.support.datauriallowed || page <= 0 || page > this.fluidbook.settings.pages) {
             callback();
             return;
         }
diff --git a/js/libs/fluidbook/fluidbook.pagetransitions.js b/js/libs/fluidbook/fluidbook.pagetransitions.js
index 38f21ccd..89274898 100644
--- a/js/libs/fluidbook/fluidbook.pagetransitions.js
+++ b/js/libs/fluidbook/fluidbook.pagetransitions.js
@@ -65,14 +65,14 @@ FluidbookPageTransition.prototype = {
         if (this.fluidbook.settings.mobileTransitions === 'slide') {
             return 'slide';
         }
-        if (!this.fluidbook.support.transitions3dacc) {
+        if (!this.fluidbook.support.transitions3dacc || !this.fluidbook.support.datauriallowed) {
             if (!this.fluidbook.support.transitions3d) {
                 return 'slide';
             } else {
                 return 'flipcss';
             }
         }
-        if (this.fluidbook.support.transitions3dacc && this.fluidbook.settings.mobileTransitions === 'flip3d') {
+        if (this.fluidbook.support.transitions3dacc && this.fluidbook.settings.mobileTransitions === 'flip3d' && this.fluidbook.support.datauriallowed) {
             return 'flip3d';
         }
         return 'flipcss';
diff --git a/js/libs/fluidbook/fluidbook.support.js b/js/libs/fluidbook/fluidbook.support.js
index 0befbfc9..ddab074b 100644
--- a/js/libs/fluidbook/fluidbook.support.js
+++ b/js/libs/fluidbook/fluidbook.support.js
@@ -1,5 +1,6 @@
 function FluidbookSupport(fluidbook) {
     this.fluidbook = fluidbook;
+    this.testDataURILoading();
     this.userAgent = navigator.userAgent;
     this.IE = 0;
     try {
@@ -66,6 +67,21 @@ function FluidbookSupport(fluidbook) {
 }
 
 FluidbookSupport.prototype = {
+    testDataURILoading: function () {
+        var img = new Image();
+        var $this = this;
+        $(img).on('error', function () {
+            $this.datauriallowed = false;
+        });
+        $(img).on('load', function () {
+            $this.datauriallowed = true;
+        });
+        try {
+            img.src = 'data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7';
+        } catch (err) {
+            $this.datauriallowed = false;
+        }
+    },
     getTransitionEndEvent: function (all) {
         if (all == undefined) {
             all = false;
-- 
2.39.5