Fixed issue #2976 - Not possible to copy inline images text from article to article (copy text and image image - via clipboard ctrl+c/ctrl+v).

app/assets/javascripts/app/lib/app_post/utils.coffee

@@ -1217,25 +1217,38 @@ class App.Utils
     )
     html.get(0).innerHTML
 
-  @_htmlImage2DataUrl: (img) ->
+  @_htmlImage2DataUrl: (img, params = {}) ->
     canvas = document.createElement('canvas')
     canvas.width = img.width
     canvas.height = img.height
     ctx = canvas.getContext('2d')
     ctx.drawImage(img, 0, 0)
-    canvas.toDataURL('image/png')
+    try
+      data = canvas.toDataURL('image/png')
+      params.success(img, data) if params.success
+      return data
+    catch e
+      App.Log.notice('Utils', "Can\'t insert image from #{img.src}", e)
+      params.fail(img) if params.fail
+    return
 
-  @htmlImage2DataUrlAsyncInline: (html, callback) ->
+  # convert image urls info data urls in element
+  @htmlImage2DataUrlAsyncInline: (html, params = {}) ->
     html.find('img').each( (index) ->
       element = $(@)
       src = element.attr('src')
 
       # <img src="cid: ..."> or an empty src attribute may mean broken emails (see issue #2305 / #2701)
       return if !src? or src.match(/^(data|cid):/i)
-
-      App.Utils._htmlImage2DataUrlAsync(@, (data) ->
-        element.attr('src', data)
-        callback(element) if callback
+      App.Utils._htmlImage2DataUrlAsync(@,
+        success: (img, data) ->
+          $img = $(img)
+          $img.attr('src', data)
+          $img.css('max-width','100%')
+          params.success(img, data) if params.success
+        fail: (img) ->
+          img.remove()
+          params.fail(img) if params.fail
       )
     )
 
@@ -1253,7 +1266,7 @@ class App.Utils
 
     cacheOrDone = ->
       if (nextElem = elems.pop())
-        App.Utils._htmlImage2DataUrlAsync(nextElem, (data) ->
+        App.Utils._htmlImage2DataUrlAsync(nextElem, success: (data) ->
           $(nextElem).attr('src', data)
           cacheOrDone()
         )
@@ -1262,12 +1275,14 @@ class App.Utils
 
     cacheOrDone()
 
-  @_htmlImage2DataUrlAsync: (originalImage, callback) ->
+  @_htmlImage2DataUrlAsync: (originalImage, params = {}) ->
     imageCache = new Image()
+    imageCache.crossOrigin = 'anonymous'
     imageCache.onload = ->
-      data = App.Utils._htmlImage2DataUrl(originalImage)
-      callback(data) if callback
-
+      App.Utils._htmlImage2DataUrl(originalImage, params)
+    imageCache.onerror = ->
+      App.Log.notice('Utils', "Unable to load image from #{originalImage.src}")
+      params.fail(originalImage) if params.fail
     imageCache.src = originalImage.src
 
   @baseUrl: ->

app/assets/javascripts/app/lib/base/jquery.contenteditable.js

@@ -382,6 +382,7 @@
       if (htmlString) {
         this.log('insert html from clipboard', htmlString)
         this.paste(htmlString)
+        App.Utils.htmlImage2DataUrlAsyncInline(this.$element)
         return true
       }
     }

public/assets/tests/html_utils.js

@@ -3278,13 +3278,19 @@ $('#image2data1 img').one('load', htmlImage2DataUrlTest1)
 
 var source2 = '<img src="/assets/images/chat-demo-avatar.png">some test'
 $('#image2data2').html(source2)
-var htmlImage2DataUrlTest2 = function(element) {
-  test("htmlImage2DataUrl2 async", function() {
-    ok(!element.html().match(/chat-demo-avatar/), source2)
-    ok(element.get(0).outerHTML.match(/^\<img src=\"data:image\/png;base64,/), source2)
+var htmlImage2DataUrlTest2Success = function(element) {
+  test('htmlImage2DataUrl2 async', function() {
+    ok(!$(element).html().match(/chat-demo-avatar/), source2)
+    ok($(element).get(0).outerHTML.match(/^\<img src=\"data:image\/png;base64,/), source2)
+    ok($(element).attr('style'), 'max-width: 100%;')
   });
 }
-App.Utils.htmlImage2DataUrlAsyncInline($('#image2data2'), htmlImage2DataUrlTest2)
+var htmlImage2DataUrlTest2Fail = function() {
+  test('htmlImage2DataUrl2 async', function() {
+    ok(false, 'fail callback is exectuted!')
+  });
+}
+App.Utils.htmlImage2DataUrlAsyncInline($('#image2data2'), {success: htmlImage2DataUrlTest2Success, fail: htmlImage2DataUrlTest2Fail})
 
 }