<p dir="auto">Check this: <a href="http://plumdesigns.tk/dch/#about-us" rel="nofollow">http://plumdesigns.tk/dch/#about-us</a></p>
<p dir="auto">Click on View Portfolio button in About Us Section, you will see that scrollbars hides and fixed sidebar and header change its position.</p>
<p dir="auto">Is this problem with Modal or I am doing something wrong?</p>
<p dir="auto">re: <a class="issue-link js-issue-link" data-error-text="Failed to load title" data-id="18248472" data-permission-text="Title is private" data-url="https://github.com/twbs/bootstrap/issues/9855" data-hovercard-type="issue" data-hovercard-url="/twbs/bootstrap/issues/9855/hovercard" href="https://github.com/twbs/bootstrap/issues/9855">#9855</a><br>
in 3.2.0, when body has a scrollbar, it's content now stays in place when modal is opened (padding is added to the body).<br>
But fixed top navbar, having position: fixed, left: 0 and right: 0, now jumps to the right when modal is opened, as it ignores padding-right on the body.</p>