diff --git a/browser/extensions/pdfjs/README.mozilla b/browser/extensions/pdfjs/README.mozilla
index 931fe46a7a4a..64b69962cf50 100644
--- a/browser/extensions/pdfjs/README.mozilla
+++ b/browser/extensions/pdfjs/README.mozilla
@@ -1,3 +1,3 @@
 This is the pdf.js project output, https://github.com/mozilla/pdf.js
 
-Current extension version is: 1.1.114
+Current extension version is: 1.1.165
diff --git a/browser/extensions/pdfjs/content/build/pdf.js b/browser/extensions/pdfjs/content/build/pdf.js
index 681e85baf3b9..52c77b7dc71e 100644
--- a/browser/extensions/pdfjs/content/build/pdf.js
+++ b/browser/extensions/pdfjs/content/build/pdf.js
@@ -22,8 +22,8 @@ if (typeof PDFJS === 'undefined') {
   (typeof window !== 'undefined' ? window : this).PDFJS = {};
 }
 
-PDFJS.version = '1.1.114';
-PDFJS.build = '3fd44fd';
+PDFJS.version = '1.1.165';
+PDFJS.build = '39d2103';
 
 (function pdfjsWrapper() {
   // Use strict in our context only - users might not want it
@@ -919,6 +919,10 @@ function stringToUTF8String(str) {
   return decodeURIComponent(escape(str));
 }
 
+function utf8StringToString(str) {
+  return unescape(encodeURIComponent(str));
+}
+
 function isEmptyObj(obj) {
   for (var key in obj) {
     return false;
@@ -2009,6 +2013,7 @@ var PDFPageProxy = (function PDFPageProxyClosure() {
                                                       this.commonObjs,
                                                       intentState.operatorList,
                                                       this.pageNumber);
+      internalRenderTask.useRequestAnimationFrame = renderingIntent !== 'print';
       if (!intentState.renderTasks) {
         intentState.renderTasks = [];
       }
@@ -2814,6 +2819,7 @@ var InternalRenderTask = (function InternalRenderTaskClosure() {
     this.running = false;
     this.graphicsReadyCallback = null;
     this.graphicsReady = false;
+    this.useRequestAnimationFrame = false;
     this.cancelled = false;
     this.capability = createPromiseCapability();
     this.task = new RenderTask(this);
@@ -2887,7 +2893,11 @@ var InternalRenderTask = (function InternalRenderTaskClosure() {
     },
 
     _scheduleNext: function InternalRenderTask__scheduleNext() {
-      window.requestAnimationFrame(this._nextBound);
+      if (this.useRequestAnimationFrame) {
+        window.requestAnimationFrame(this._nextBound);
+      } else {
+        Promise.resolve(undefined).then(this._nextBound);
+      }
     },
 
     _next: function InternalRenderTask__next() {
diff --git a/browser/extensions/pdfjs/content/build/pdf.worker.js b/browser/extensions/pdfjs/content/build/pdf.worker.js
index 9a0a0a792e70..3c6b1301ebe5 100644
--- a/browser/extensions/pdfjs/content/build/pdf.worker.js
+++ b/browser/extensions/pdfjs/content/build/pdf.worker.js
@@ -22,8 +22,8 @@ if (typeof PDFJS === 'undefined') {
   (typeof window !== 'undefined' ? window : this).PDFJS = {};
 }
 
-PDFJS.version = '1.1.114';
-PDFJS.build = '3fd44fd';
+PDFJS.version = '1.1.165';
+PDFJS.build = '39d2103';
 
 (function pdfjsWrapper() {
   // Use strict in our context only - users might not want it
@@ -919,6 +919,10 @@ function stringToUTF8String(str) {
   return decodeURIComponent(escape(str));
 }
 
+function utf8StringToString(str) {
+  return unescape(encodeURIComponent(str));
+}
+
 function isEmptyObj(obj) {
   for (var key in obj) {
     return false;
@@ -3583,12 +3587,13 @@ var XRef = (function XRefClosure() {
           trailers.push(position);
           position += skipUntil(buffer, position, startxrefBytes);
         } else if ((m = /^(\d+)\s+(\d+)\s+obj\b/.exec(token))) {
-          this.entries[m[1]] = {
-            offset: position,
-            gen: m[2] | 0,
-            uncompressed: true
-          };
-
+          if (typeof this.entries[m[1]] === 'undefined') {
+            this.entries[m[1]] = {
+              offset: position,
+              gen: m[2] | 0,
+              uncompressed: true
+            };
+          }
           var contentLength = skipUntil(buffer, position, endobjBytes) + 7;
           var content = buffer.subarray(position, position + contentLength);
 
@@ -4811,7 +4816,15 @@ var LinkAnnotation = (function LinkAnnotationClosure() {
         if (!isValidUrl(url, false)) {
           url = '';
         }
-        data.url = url;
+        // According to ISO 32000-1:2008, section 12.6.4.7, 
+        // URI should to be encoded in 7-bit ASCII.
+        // Some bad PDFs may have URIs in UTF-8 encoding, see Bugzilla 1122280.
+        try {
+          data.url = stringToUTF8String(url);
+        } catch (e) {
+          // Fall back to a simple copy.
+          data.url = url;
+        }
       } else if (linkType === 'GoTo') {
         data.dest = action.get('D');
       } else if (linkType === 'GoToR') {
@@ -9094,6 +9107,14 @@ var CipherTransformFactory = (function CipherTransformFactoryClosure() {
     var fileIdBytes = stringToBytes(fileId);
     var passwordBytes;
     if (password) {
+      if (revision === 6) {
+        try {
+          password = utf8StringToString(password);
+        } catch (ex) {
+          warn('CipherTransformFactory: ' +
+               'Unable to convert UTF8 encoded password.');
+        }
+      }
       passwordBytes = stringToBytes(password);
     }
 
@@ -9198,7 +9219,7 @@ var CipherTransformFactory = (function CipherTransformFactoryClosure() {
 
   CipherTransformFactory.prototype = {
     createCipherTransform:
-      function CipherTransformFactory_createCipherTransform(num, gen) {
+        function CipherTransformFactory_createCipherTransform(num, gen) {
       if (this.algorithm === 4 || this.algorithm === 5) {
         return new CipherTransform(
           buildCipherConstructor(this.cf, this.stmf,
@@ -10932,6 +10953,17 @@ var PartialEvaluator = (function PartialEvaluatorClosure() {
           var tsm = [textState.fontSize * textState.textHScale, 0,
                      0, textState.fontSize,
                      0, textState.textRise];
+
+          if (font.isType3Font &&
+              textState.fontMatrix !== FONT_IDENTITY_MATRIX &&
+              textState.fontSize === 1) {
+            var glyphHeight = font.bbox[3] - font.bbox[1];
+            if (glyphHeight > 0) {
+              glyphHeight = glyphHeight * textState.fontMatrix[3];
+              tsm[3] *= glyphHeight;
+            }
+          }
+
           var trm = textChunk.transform = Util.transform(textState.ctm,
                                     Util.transform(textState.textMatrix, tsm));
           if (!font.vertical) {
@@ -10985,16 +11017,23 @@ var PartialEvaluator = (function PartialEvaluatorClosure() {
           // var x = pt[0];
           // var y = pt[1];
 
+          var charSpacing = 0;
+          if (textChunk.str.length > 0) {
+            // Apply char spacing only when there are chars.
+            // As a result there is only spacing between glyphs.
+            charSpacing = textState.charSpacing;
+          }
+
           var tx = 0;
           var ty = 0;
           if (!font.vertical) {
             var w0 = glyphWidth * textState.fontMatrix[0];
-            tx = (w0 * textState.fontSize + textState.charSpacing) *
+            tx = (w0 * textState.fontSize + charSpacing) *
                  textState.textHScale;
             width += tx;
           } else {
             var w1 = glyphWidth * textState.fontMatrix[0];
-            ty = w1 * textState.fontSize + textState.charSpacing;
+            ty = w1 * textState.fontSize + charSpacing;
             height += ty;
           }
           textState.translateTextMatrix(tx, ty);
@@ -11260,8 +11299,13 @@ var PartialEvaluator = (function PartialEvaluatorClosure() {
               var data = diffEncoding[j];
               if (isNum(data)) {
                 index = data;
-              } else {
+              } else if (isName(data)) {
                 differences[index++] = data.name;
+              } else if (isRef(data)) {
+                diffEncoding[j--] = xref.fetch(data);
+                continue;
+              } else {
+                error('Invalid entry in \'Differences\' array: ' + data);
               }
             }
           }
@@ -11610,6 +11654,7 @@ var PartialEvaluator = (function PartialEvaluatorClosure() {
           // is a tagged pdf. Create a barbebones one to get by.
           descriptor = new Dict(null);
           descriptor.set('FontName', Name.get(type));
+          descriptor.set('FontBBox', dict.get('FontBBox'));
         } else {
           // Before PDF 1.5 if the font was one of the base 14 fonts, having a
           // FontDescriptor was not required.
@@ -16029,6 +16074,7 @@ var Font = (function FontClosure() {
     this.ascent = properties.ascent / PDF_GLYPH_SPACE_UNITS;
     this.descent = properties.descent / PDF_GLYPH_SPACE_UNITS;
     this.fontMatrix = properties.fontMatrix;
+    this.bbox = properties.bbox;
 
     this.toUnicode = properties.toUnicode = this.buildToUnicode(properties);
 
@@ -16840,7 +16886,10 @@ var Font = (function FontClosure() {
           }
         }
 
-        if (!potentialTable) {
+        if (potentialTable) {
+          font.pos = start + potentialTable.offset;
+        }
+        if (!potentialTable || font.peekByte() === -1) {
           warn('Could not find a preferred cmap table.');
           return {
             platformId: -1,
@@ -16850,7 +16899,6 @@ var Font = (function FontClosure() {
           };
         }
 
-        font.pos = start + potentialTable.offset;
         var format = font.getUint16();
         var length = font.getUint16();
         var language = font.getUint16();
@@ -17285,6 +17333,9 @@ var Font = (function FontClosure() {
           default:
             warn('Unknown/unsupported post table version ' + version);
             valid = false;
+            if (properties.defaultEncoding) {
+              glyphNames = properties.defaultEncoding;
+            }
             break;
         }
         properties.glyphNames = glyphNames;
diff --git a/browser/extensions/pdfjs/content/web/viewer.css b/browser/extensions/pdfjs/content/web/viewer.css
index bf57df853431..80f7d6215bf8 100644
--- a/browser/extensions/pdfjs/content/web/viewer.css
+++ b/browser/extensions/pdfjs/content/web/viewer.css
@@ -1172,7 +1172,6 @@ html[dir='rtl'] .verticalToolbarSeparator {
 }
 
 .thumbnailImage {
-  transition-duration: 150ms;
   border: 1px solid transparent;
   box-shadow: 0 0 0 1px rgba(0, 0, 0, 0.5), 0 2px 8px rgba(0, 0, 0, 0.3);
   opacity: 0.8;
@@ -1184,7 +1183,6 @@ html[dir='rtl'] .verticalToolbarSeparator {
 .thumbnailSelectionRing {
   border-radius: 2px;
   padding: 7px;
-  transition-duration: 150ms;
 }
 
 a:focus > .thumbnail > .thumbnailSelectionRing > .thumbnailImage,
@@ -1400,10 +1398,6 @@ html[dir='rtl'] .attachmentsItem > button {
 .dialog .toolbarField {
   margin: 5px 0;
 }
-.dialog .toolbarField:hover,
-.dialog .toolbarField:focus {
-  border-color: hsla(0,0%,0%,.32) hsla(0,0%,0%,.38) hsla(0,0%,0%,.42);
-}
 
 .dialog .separator {
   display: block;
@@ -1750,10 +1744,14 @@ html[dir='rtl'] #documentPropertiesOverlay .row > * {
   body[data-mozPrintCallback] #printContainer {
     display: block;
   }
-  #printContainer canvas {
+  /* wrapper around (scaled) print canvas elements */
+  #printContainer > div {
     position: relative;
     top: 0;
     left: 0;
+    overflow: hidden;
+  }
+  #printContainer canvas {
     display: block;
   }
 }
diff --git a/browser/extensions/pdfjs/content/web/viewer.js b/browser/extensions/pdfjs/content/web/viewer.js
index 68631c3204af..f20ed97e9a69 100644
--- a/browser/extensions/pdfjs/content/web/viewer.js
+++ b/browser/extensions/pdfjs/content/web/viewer.js
@@ -3520,10 +3520,15 @@ var PDFPageView = (function PDFPageViewClosure() {
       // better output until bug 811002 is fixed in FF.
       var PRINT_OUTPUT_SCALE = 2;
       var canvas = document.createElement('canvas');
+
+      // The logical size of the canvas.
       canvas.width = Math.floor(viewport.width) * PRINT_OUTPUT_SCALE;
       canvas.height = Math.floor(viewport.height) * PRINT_OUTPUT_SCALE;
-      canvas.style.width = (PRINT_OUTPUT_SCALE * viewport.width) + 'pt';
-      canvas.style.height = (PRINT_OUTPUT_SCALE * viewport.height) + 'pt';
+
+      // The rendered size of the canvas, relative to the size of canvasWrapper.
+      canvas.style.width = (PRINT_OUTPUT_SCALE * 100) + '%';
+      canvas.style.height = (PRINT_OUTPUT_SCALE * 100) + '%';
+
       var cssScale = 'scale(' + (1 / PRINT_OUTPUT_SCALE) + ', ' +
                                 (1 / PRINT_OUTPUT_SCALE) + ')';
       CustomStyle.setProp('transform' , canvas, cssScale);
@@ -4201,11 +4206,11 @@ var PDFViewer = (function pdfViewer() {
 
   PDFViewer.prototype = /** @lends PDFViewer.prototype */{
     get pagesCount() {
-      return this.pages.length;
+      return this._pages.length;
     },
 
     getPageView: function (index) {
-      return this.pages[index];
+      return this._pages[index];
     },
 
     get currentPageNumber() {
@@ -4289,9 +4294,9 @@ var PDFViewer = (function pdfViewer() {
     set pagesRotation(rotation) {
       this._pagesRotation = rotation;
 
-      for (var i = 0, l = this.pages.length; i < l; i++) {
-        var page = this.pages[i];
-        page.update(page.scale, rotation);
+      for (var i = 0, l = this._pages.length; i < l; i++) {
+        var pageView = this._pages[i];
+        pageView.update(pageView.scale, rotation);
       }
 
       this._setScale(this._currentScaleValue, true);
@@ -4373,7 +4378,7 @@ var PDFViewer = (function pdfViewer() {
             annotationsLayerFactory: this
           });
           bindOnAfterAndBeforeDraw(pageView);
-          this.pages.push(pageView);
+          this._pages.push(pageView);
         }
 
         // Fetch all the pages since the viewport is needed before printing
@@ -4384,7 +4389,7 @@ var PDFViewer = (function pdfViewer() {
             var getPagesLeft = pagesCount;
             for (var pageNum = 1; pageNum <= pagesCount; ++pageNum) {
               pdfDocument.getPage(pageNum).then(function (pageNum, pdfPage) {
-                var pageView = self.pages[pageNum - 1];
+                var pageView = self._pages[pageNum - 1];
                 if (!pageView.pdfPage) {
                   pageView.setPdfPage(pdfPage);
                 }
@@ -4417,12 +4422,12 @@ var PDFViewer = (function pdfViewer() {
     },
 
     _resetView: function () {
-      this.pages = [];
+      this._pages = [];
       this._currentPageNumber = 1;
       this._currentScale = UNKNOWN_SCALE;
       this._currentScaleValue = null;
       this._buffer = new PDFPageViewBuffer(DEFAULT_CACHE_SIZE);
-      this.location = null;
+      this._location = null;
       this._pagesRotation = 0;
       this._pagesRequests = [];
 
@@ -4437,8 +4442,8 @@ var PDFViewer = (function pdfViewer() {
         return;
       }
       this.update();
-      for (var i = 0, ii = this.pages.length; i < ii; i++) {
-        this.pages[i].updatePosition();
+      for (var i = 0, ii = this._pages.length; i < ii; i++) {
+        this._pages[i].updatePosition();
       }
     },
 
@@ -4463,18 +4468,18 @@ var PDFViewer = (function pdfViewer() {
         return;
       }
 
-      for (var i = 0, ii = this.pages.length; i < ii; i++) {
-        this.pages[i].update(newScale);
+      for (var i = 0, ii = this._pages.length; i < ii; i++) {
+        this._pages[i].update(newScale);
       }
       this._currentScale = newScale;
 
       if (!noScroll) {
         var page = this._currentPageNumber, dest;
-        if (this.location && !IGNORE_CURRENT_POSITION_ON_ZOOM &&
+        if (this._location && !IGNORE_CURRENT_POSITION_ON_ZOOM &&
             !(this.isInPresentationMode || this.isChangingPresentationMode)) {
-          page = this.location.pageNumber;
-          dest = [null, { name: 'XYZ' }, this.location.left,
-            this.location.top, null];
+          page = this._location.pageNumber;
+          dest = [null, { name: 'XYZ' }, this._location.left,
+                  this._location.top, null];
         }
         this.scrollPageIntoView(page, dest);
       }
@@ -4491,7 +4496,7 @@ var PDFViewer = (function pdfViewer() {
       if (scale > 0) {
         this._setScaleUpdatePages(scale, value, noScroll, false);
       } else {
-        var currentPage = this.pages[this._currentPageNumber - 1];
+        var currentPage = this._pages[this._currentPageNumber - 1];
         if (!currentPage) {
           return;
         }
@@ -4541,7 +4546,7 @@ var PDFViewer = (function pdfViewer() {
      */
     scrollPageIntoView: function PDFViewer_scrollPageIntoView(pageNumber,
                                                               dest) {
-      var pageView = this.pages[pageNumber - 1];
+      var pageView = this._pages[pageNumber - 1];
 
       if (this.isInPresentationMode) {
         if (this.linkService.page !== pageView.id) {
@@ -4644,7 +4649,7 @@ var PDFViewer = (function pdfViewer() {
       var pageNumber = firstPage.id;
       var pdfOpenParams = '#page=' + pageNumber;
       pdfOpenParams += '&zoom=' + normalizedScaleValue;
-      var currentPageView = this.pages[pageNumber - 1];
+      var currentPageView = this._pages[pageNumber - 1];
       var container = this.container;
       var topLeft = currentPageView.getPagePoint(
         (container.scrollLeft - firstPage.x),
@@ -4653,7 +4658,7 @@ var PDFViewer = (function pdfViewer() {
       var intTop = Math.round(topLeft[1]);
       pdfOpenParams += ',' + intLeft + ',' + intTop;
 
-      this.location = {
+      this._location = {
         pageNumber: pageNumber,
         scale: normalizedScaleValue,
         top: intTop,
@@ -4707,6 +4712,7 @@ var PDFViewer = (function pdfViewer() {
 
       var event = document.createEvent('UIEvents');
       event.initUIEvent('updateviewarea', true, true, window, 0);
+      event.location = this._location;
       this.container.dispatchEvent(event);
     },
 
@@ -4733,22 +4739,22 @@ var PDFViewer = (function pdfViewer() {
 
     _getVisiblePages: function () {
       if (!this.isInPresentationMode) {
-        return getVisibleElements(this.container, this.pages, true);
+        return getVisibleElements(this.container, this._pages, true);
       } else {
         // The algorithm in getVisibleElements doesn't work in all browsers and
         // configurations when presentation mode is active.
         var visible = [];
-        var currentPage = this.pages[this._currentPageNumber - 1];
+        var currentPage = this._pages[this._currentPageNumber - 1];
         visible.push({ id: currentPage.id, view: currentPage });
         return { first: currentPage, last: currentPage, views: visible };
       }
     },
 
     cleanup: function () {
-      for (var i = 0, ii = this.pages.length; i < ii; i++) {
-        if (this.pages[i] &&
-          this.pages[i].renderingState !== RenderingStates.FINISHED) {
-          this.pages[i].reset();
+      for (var i = 0, ii = this._pages.length; i < ii; i++) {
+        if (this._pages[i] &&
+            this._pages[i].renderingState !== RenderingStates.FINISHED) {
+          this._pages[i].reset();
         }
       }
     },
@@ -4779,7 +4785,7 @@ var PDFViewer = (function pdfViewer() {
     forceRendering: function (currentlyVisiblePages) {
       var visiblePages = currentlyVisiblePages || this._getVisiblePages();
       var pageView = this.renderingQueue.getHighestPriority(visiblePages,
-                                                            this.pages,
+                                                            this._pages,
                                                             this.scroll.down);
       if (pageView) {
         this._ensurePdfPageLoaded(pageView).then(function () {
@@ -5042,12 +5048,11 @@ var PDFThumbnailView = (function PDFThumbnailViewClosure() {
     /**
      * @private
      */
-    _getPageDrawContext: function PDFThumbnailView_getPageDrawContext() {
+    _getPageDrawContext:
+        function PDFThumbnailView_getPageDrawContext(noCtxScale) {
       var canvas = document.createElement('canvas');
       canvas.id = this.renderingId;
 
-      canvas.width = this.canvasWidth;
-      canvas.height = this.canvasHeight;
       canvas.className = 'thumbnailImage';
       canvas.setAttribute('aria-label', mozL10n.get('thumb_page_canvas',
         {page: this.id}, 'Thumbnail of Page {{page}}'));
@@ -5056,7 +5061,16 @@ var PDFThumbnailView = (function PDFThumbnailViewClosure() {
       this.div.setAttribute('data-loaded', true);
       this.ring.appendChild(canvas);
 
-      return canvas.getContext('2d');
+      var ctx = canvas.getContext('2d');
+      var outputScale = getOutputScale(ctx);
+      canvas.width = (this.canvasWidth * outputScale.sx) | 0;
+      canvas.height = (this.canvasHeight * outputScale.sy) | 0;
+      canvas.style.width = this.canvasWidth + 'px';
+      canvas.style.height = this.canvasHeight + 'px';
+      if (!noCtxScale && outputScale.scaled) {
+        ctx.scale(outputScale.sx, outputScale.sy);
+      }
+      return ctx;
     },
 
     draw: function PDFThumbnailView_draw() {
@@ -5139,7 +5153,7 @@ var PDFThumbnailView = (function PDFThumbnailViewClosure() {
       this.hasImage = true;
       this.renderingState = RenderingStates.FINISHED;
 
-      var ctx = this._getPageDrawContext();
+      var ctx = this._getPageDrawContext(true);
       var canvas = ctx.canvas;
 
       if (img.width <= 2 * canvas.width) {
@@ -5739,7 +5753,7 @@ var PDFViewerApplication = {
       newScale = (newScale * DEFAULT_SCALE_DELTA).toFixed(2);
       newScale = Math.ceil(newScale * 10) / 10;
       newScale = Math.min(MAX_SCALE, newScale);
-    } while (--ticks && newScale < MAX_SCALE);
+    } while (--ticks > 0 && newScale < MAX_SCALE);
     this.setScale(newScale, true);
   },
 
@@ -5749,7 +5763,7 @@ var PDFViewerApplication = {
       newScale = (newScale / DEFAULT_SCALE_DELTA).toFixed(2);
       newScale = Math.floor(newScale * 10) / 10;
       newScale = Math.max(MIN_SCALE, newScale);
-    } while (--ticks && newScale > MIN_SCALE);
+    } while (--ticks > 0 && newScale > MIN_SCALE);
     this.setScale(newScale, true);
   },
 
@@ -6691,6 +6705,35 @@ var PDFViewerApplication = {
 
     var body = document.querySelector('body');
     body.setAttribute('data-mozPrintCallback', true);
+
+    if (!this.hasEqualPageSizes) {
+      console.warn('Not all pages have the same size. The printed result ' +
+          'may be incorrect!');
+    }
+
+    // Insert a @page + size rule to make sure that the page size is correctly
+    // set. Note that we assume that all pages have the same size, because
+    // variable-size pages are not supported yet (at least in Chrome & Firefox).
+    // TODO(robwu): Use named pages when size calculation bugs get resolved
+    // (e.g. https://crbug.com/355116) AND when support for named pages is
+    // added (http://www.w3.org/TR/css3-page/#using-named-pages).
+    // In browsers where @page + size is not supported (such as Firefox,
+    // https://bugzil.la/851441), the next stylesheet will be ignored and the
+    // user has to select the correct paper size in the UI if wanted.
+    this.pageStyleSheet = document.createElement('style');
+    var pageSize = this.pdfViewer.getPageView(0).pdfPage.getViewport(1);
+    this.pageStyleSheet.textContent =
+      // "size:<width> <height>" is what we need. But also add "A4" because
+      // Firefox incorrectly reports support for the other value.
+      '@supports ((size:A4) and (size:1pt 1pt)) {' +
+      '@page { size: ' + pageSize.width + 'pt ' + pageSize.height + 'pt;}' +
+      // The canvas and each ancestor node must have a height of 100% to make
+      // sure that each canvas is printed on exactly one page.
+      '#printContainer {height:100%}' +
+      '#printContainer > div {width:100% !important;height:100% !important;}' +
+      '}';
+    body.appendChild(this.pageStyleSheet);
+
     for (i = 0, ii = this.pagesCount; i < ii; ++i) {
       this.pdfViewer.getPageView(i).beforePrint();
     }
@@ -6700,12 +6743,30 @@ var PDFViewerApplication = {
     }));
   },
 
+  // Whether all pages of the PDF have the same width and height.
+  get hasEqualPageSizes() {
+    var firstPage = this.pdfViewer.getPageView(0);
+    for (var i = 1, ii = this.pagesCount; i < ii; ++i) {
+      var pageView = this.pdfViewer.getPageView(i);
+      if (pageView.width !== firstPage.width ||
+          pageView.height !== firstPage.height) {
+        return false;
+      }
+    }
+    return true;
+  },
+
   afterPrint: function pdfViewSetupAfterPrint() {
     var div = document.getElementById('printContainer');
     while (div.hasChildNodes()) {
       div.removeChild(div.lastChild);
     }
 
+    if (this.pageStyleSheet && this.pageStyleSheet.parentNode) {
+      this.pageStyleSheet.parentNode.removeChild(this.pageStyleSheet);
+      this.pageStyleSheet = null;
+    }
+
     this.printing = false;
     this.forceRendering();
   },
@@ -7009,12 +7070,11 @@ function updateViewarea() {
   PDFViewerApplication.pdfViewer.update();
 }
 
-window.addEventListener('updateviewarea', function () {
+window.addEventListener('updateviewarea', function (evt) {
   if (!PDFViewerApplication.initialized) {
     return;
   }
-
-  var location = PDFViewerApplication.pdfViewer.location;
+  var location = evt.location;
 
   PDFViewerApplication.store.initializedPromise.then(function() {
     PDFViewerApplication.store.setMultiple({