Fix image/video hover in case where dimensions are not available. #2197

src/Images/ImageHover.coffee

@@ -46,20 +46,22 @@ ImageHover =
       if Conf['Autoplay']
         el.play()
         @currentTime = el.currentTime if @nodeName is 'VIDEO'
-    [width, height] = (+x for x in file.dimensions.split 'x')
-    {left, right} = @getBoundingClientRect()
-    maxWidth = doc.clientWidth
-    maxHeight = doc.clientHeight - UI.hover.padding
-    scale = Math.min 1, maxWidth / width, maxHeight / height
-    el.style.maxWidth  = "#{scale * width}px"
-    el.style.maxHeight = "#{scale * height}px"
+    if file.dimensions
+      [width, height] = (+x for x in file.dimensions.split 'x')
+      maxWidth = doc.clientWidth
+      maxHeight = doc.clientHeight - UI.hover.padding
+      scale = Math.min 1, maxWidth / width, maxHeight / height
+      width *= scale
+      height *= scale
+      el.style.maxWidth  = "#{width}px"
+      el.style.maxHeight = "#{height}px"
     UI.hover
       root: @
       el: el
       latestEvent: e
       endEvents: 'mouseout click'
-      height: scale * height
-      width: scale * width
+      height: height
+      width: width
       noRemove: true
       cb: ->
         $.off el, 'error', error

src/css/style.css

@@ -1350,6 +1350,10 @@ span.hide-announcement {
 }
 #ihover {
   pointer-events: none;
+  /* XXX https://code.google.com/p/chromium/issues/detail?id=168840, https://bugs.webkit.org/show_bug.cgi?id=94158 */
+  max-height: 95vh;
+  max-height: calc(100vh - 25px);
+  max-width: 100vw;
 }
 /* WEBM Metadata */
 .webm-title > a::before {