IE6-10: ENTER key immediately after an anchor generates javascript error

[hel]

Assume the following content is within the ckeditor:

    Here is an anchor [anchor] in some text

where [anchor] is the anchor placeholder.

On IE9, if you place the cursor immediately after the anchor and then hit ENTER, it is possible to generate an "Unable to get value of the property 'insertBeforeMe': object is null or undefined" javascript error. See screen shot.

Also managed to recreate in one of the nightly build samples: ​http://nightly.ckeditor.com/7382/_samples/replacebyclass.html

[hel]

IE9 ENTER key after anchor js error

[Jakub Ś]

1. Insert below code:

   <p>
   	Here is an anchor&nbsp;<a name="abc"></a> in some text</p>
   

2. Place cursor after anchor and press enter

IE9-IE10
Message: Unable to get value of the property 'insertBeforeMe Line: 163
URI: /ckeditor/_source/core/dom/range.js

IE6-8
Message: 'getFirst()' in null or not an object
Line: 163
URI: /ckeditor/_source/core/dom/range.js

Reproducible in all IE's from CKEditor 3.6 rev [6904]

[Jakub Ś]

Same error but diffrent TC and different version #8395

[Piotrek Koszuliński]

Not reproducible on 4.3 (I checked IE8 and IE9).