I have answer you already in the support ticket:
Officially IE11 is not supported and that is the reason that your code does not work as you expect. There is a easy workaround - you just need to add the following meta-tag in the page head:
This should be added under:
- <your page> with the navigation widget
- Title and properties menu
- add the code above in section 'HTML included in the <head> tag (except title, keywords, description)'
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