diff --git a/core/editable.js b/core/editable.js
index e25cc77e5fe..1e01c3f574d 100644
--- a/core/editable.js
+++ b/core/editable.js
@@ -1619,7 +1619,7 @@
 
 			var context = that.blockLimit.getName();
 
-			// Wrap data to be inserted, to avoid loosing leading whitespaces
+			// Wrap data to be inserted, to avoid losing leading whitespaces
 			// when going through the below procedure.
 			if ( /^\s+|\s+$/.test( data ) && 'span' in CKEDITOR.dtd[ context ] ) {
 				var protect = '<span data-cke-marker="1">&nbsp;</span>';
@@ -1632,6 +1632,7 @@
 			data = that.editor.dataProcessor.toHtml( data, {
 				context: null,
 				fixForBody: false,
+				protectedWhitespaces: !!protect,
 				dontFilter: that.dontFilter,
 				// Use the current, contextual settings.
 				filter: that.editor.activeFilter,
diff --git a/core/htmldataprocessor.js b/core/htmldataprocessor.js
index f5c25993f61..451bbd41ce8 100644
--- a/core/htmldataprocessor.js
+++ b/core/htmldataprocessor.js
@@ -224,11 +224,13 @@
 		 * @param {Boolean} [options.dontFilter] Do not filter data with {@link CKEDITOR.filter} (note: transformations
 		 * will be still applied).
 		 * @param {Number} [options.enterMode] When specified it will be used instead of the {@link CKEDITOR.editor#enterMode main enterMode}.
+		 * @param {Boolean} [options.protectedWhitespaces] Indicates that content has been wrapped with `span` elements to preserve
+		 * leading and trailing whitespaces. Option used by the {@link CKEDITOR.editor#insertHtml} method.
 		 * @returns {String}
 		 */
 		toHtml: function( data, options, fixForBody, dontFilter ) {
 			var editor = this.editor,
-				context, filter, enterMode;
+				context, filter, enterMode, protectedWhitespaces;
 
 			// Typeof null == 'object', so check truthiness of options too.
 			if ( options && typeof options == 'object' ) {
@@ -237,6 +239,7 @@
 				dontFilter = options.dontFilter;
 				filter = options.filter;
 				enterMode = options.enterMode;
+				protectedWhitespaces = options.protectedWhitespaces;
 			}
 			// Backward compatibility. Since CKEDITOR 4.3 every option was a separate argument.
 			else {
@@ -253,7 +256,8 @@
 				fixForBody: fixForBody,
 				dontFilter: dontFilter,
 				filter: filter || editor.filter,
-				enterMode: enterMode || editor.enterMode
+				enterMode: enterMode || editor.enterMode,
+				protectedWhitespaces: protectedWhitespaces
 			} ).dataValue;
 		},
 
@@ -989,6 +993,7 @@
  * @param {Boolean} data.dontFilter See {@link CKEDITOR.htmlDataProcessor#toHtml} The `dontFilter` argument.
  * @param {Boolean} data.filter See {@link CKEDITOR.htmlDataProcessor#toHtml} The `filter` argument.
  * @param {Boolean} data.enterMode See {@link CKEDITOR.htmlDataProcessor#toHtml} The `enterMode` argument.
+ * @param {Boolean} [data.protectedWhitespaces] See {@link CKEDITOR.htmlDataProcessor#toHtml} The `protectedWhitespaces` argument.
  */
 
 /**
diff --git a/plugins/widget/plugin.js b/plugins/widget/plugin.js
index 6dab026be33..ddf516c4d3b 100644
--- a/plugins/widget/plugin.js
+++ b/plugins/widget/plugin.js
@@ -2662,8 +2662,14 @@
 			}
 
 			// Used to determine whether only widget was pasted.
-			processedWidgetOnly = evt.data.dataValue.children.length == 1 &&
-				Widget.isParserWidgetWrapper( evt.data.dataValue.children[ 0 ] );
+			if ( evt.data.protectedWhitespaces ) {
+				// Whitespaces are protected by wrapping content with spans. Take the middle node only.
+				processedWidgetOnly = evt.data.dataValue.children.length == 3 &&
+					Widget.isParserWidgetWrapper( evt.data.dataValue.children[ 1 ] );
+			} else {
+				processedWidgetOnly = evt.data.dataValue.children.length == 1 &&
+					Widget.isParserWidgetWrapper( evt.data.dataValue.children[ 0 ] );
+			}
 		}, null, null, 8 );
 
 		editor.on( 'dataReady', function() {
diff --git a/tests/core/editable/insertion.js b/tests/core/editable/insertion.js
index f51699360e2..9f1da7c9682 100644
--- a/tests/core/editable/insertion.js
+++ b/tests/core/editable/insertion.js
@@ -134,6 +134,16 @@
 
 				assert.areSame( '<p>bar</p>', bot.editor.getData(), 'text was inserted' );
 			} );
+		},
+
+		'test insertHtml sets options.protectedWhitespaces of dP.toHtml': function() {
+			var editor = this.editor;
+
+			editor.once( 'toHtml', function( evt ) {
+				assert.isTrue( evt.data.protectedWhitespaces );
+			} );
+
+			editor.insertHtml( '  foo  ' );
 		}
 	} );
 } )();
\ No newline at end of file
diff --git a/tests/core/htmldataprocessor.js b/tests/core/htmldataprocessor.js
index d2a843aa85a..290944abd67 100644
--- a/tests/core/htmldataprocessor.js
+++ b/tests/core/htmldataprocessor.js
@@ -1010,6 +1010,16 @@
 			} ), 'br mode' );
 		},
 
+		'test toHtml options.protectedWhitespaces defaults falsy': function() {
+			var editor = this.editor;
+
+			editor.once( 'toHtml', function( evt ) {
+				assert.isUndefined( evt.data.protectedWhitespaces );
+			} );
+
+			editor.dataProcessor.toHtml( 'foo', {} );
+		},
+
 		'test leading br is removed by toDataFormat in ENTER_P and ENTER_DIV': function() {
 			var htmlDP = this.editor.dataProcessor,
 				opts = { enterMode: CKEDITOR.ENTER_P };
diff --git a/tests/plugins/widget/nestedwidgets.js b/tests/plugins/widget/nestedwidgets.js
index 236016a9009..dfe4d529a18 100644
--- a/tests/plugins/widget/nestedwidgets.js
+++ b/tests/plugins/widget/nestedwidgets.js
@@ -298,6 +298,11 @@
 
 		// #12008
 		'test pasting widget with nested editable into nested editable': function() {
+			if ( CKEDITOR.env.ie && CKEDITOR.env.version < 9 ) {
+				assert.ignore();
+				return;
+			}
+
 			var editor = this.editors.editor,
 				bot = this.editorBots.editor;
 
@@ -340,4 +345,4 @@
 			} );
 		}
 	} );
-} )();
\ No newline at end of file
+} )();