Editor Not Loading

Occasionally after submitting text, trying to reload it into the editor (to edit it after submission), the editor will not load, even though the code is the same. I can only imagine that the javascript is not loading the editor due to something to do with the text it is trying to edit.

The weird thing is, all it's trying to edit is standard html. For example:

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<div>Children&rsquo;s Sports Academies</div>
<div>&nbsp;</div>
<div>La Manga Club is the ideal place for both young and old to improve their chosen game.&nbsp; The children&rsquo;s sports academies run Monday to Friday during the main school holidays and are a fun way for children to improve their skills.</div>
<div>&nbsp;</div>
<div>Advance booking is essential and is subject to availability and minimum / maximum numbers.</div>
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Is an example of text which causes the editor to not load at all.

Any help is appreciated!