From 18e1f3d29be5adbd703a378796de0099821d7e19 Mon Sep 17 00:00:00 2001
From: Yury Delendik <ydelendik@mozilla.com>
Date: Tue, 20 Jun 2017 14:45:07 -0500
Subject: [PATCH] Ensure canvas is really hidden when used with pdfjs-dist.

Avoids black background flickering in such examples as components/simpleviewer.html
---
 web/pdf_viewer.css | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/web/pdf_viewer.css b/web/pdf_viewer.css
index 89b0b7174..dc6ff0cff 100644
--- a/web/pdf_viewer.css
+++ b/web/pdf_viewer.css
@@ -51,6 +51,10 @@
   display: block;
 }
 
+.pdfViewer .page canvas[hidden] {
+  display: none;
+}
+
 .pdfViewer .page .loadingIcon {
   position: absolute;
   display: block;