Fix TinyMCE edit link when link contains html

Description

If you have a link in tinymce like <a href=""><span>Title</span></a>, then you can edit the link. The HTML inside the link tag can be any tag.

The issue is that the selected node is the inside HTML tag instead of the link tag.

I'm not 100% keen on the solution using while but this is legacy code, so might be ok! Alternative code is welcomed :)

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