Content block in sitefinity5.0

Hi,
I am using content block in my site..its have anchor tag and the href value simply i put #tab1
but its automatically took some URL ,its happen only in internet explorer..
here my code:
<a href="#tab1" title="Overview"><span>Overview</span></a>

but its changed to below format

<a href="something/Sitefinity/Dialog/PropertyEditor?Id=981589d1-6e5a-4e5b-9f79-211ca8ee9936&amp;MediaType=0&amp;PageId=5db7b240-50a0-4d73-b4e8-8514fa0f10ae&amp;propertyValueCulture=&amp;ParentPageId=8ae20a67-a0ff-4cba-8dee-0eee07b54477&amp;hideSaveAllTranslations=true#tab1" />

please give suggestion to fix it..

thanks in advance...