Editing macros in IE 10 copies them to the top of the page

If one edits a macro by double-clicking on it in IE, after closing the box to edit that macro a copy of the macro with the edited values gets inserted on the top of the page.

I can only reproduce this with IE.10 (have not tried older IE's); Firefox and Opera work just fine. If I looked correctly then insertion of that macro already happens in the client before sending the modifications to the server.

Steps to reproduce; e.g. with http://playground.xwiki.org/xwiki/bin/view/Sandbox/WebHome

• open a page that has at least one macro with the WYSIWYG editor
• double click on the macro: this should pop up a box where one can edit values of that macro
• edit some values and press "Apply" - the box closes and one can see a "waiting" cursor while the changes are processed
• when the "waiting" cursor disappears, the page in the WYSIWYG editor gets updated
  • expected (and works in FF, Opera): macro gets updated
  • actual effect in IE: a copy of the macro is inserted at the top of the page, and this copy contains the changed values, while the original macro is unchanged