So, I have a ul list in which I click the div above it, and then I switch it so that I can expand / up the list ... but when I move the list to IE9, I see this strange effect below:

this happens when the slide module
my code is as follows:
$(".btn").click(function() { if ($(this).next().is(":visible")){ $(".slide_menu").slideUp("fast"); }else{ $(".slide_menu").slideUp("fast"); } });
html is as follows:
<div class="btn">Button</a></div> <ul class="slide_menu"> <li><a href="http://domain.com">Link</a></li> </ul>
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