problem with sticky block

Hello everyone.
I want to make a sticky block using this script

$(window).scroll(function() {
var sb_m = 80; /* top and bottom padding */
var mb = 300; /* footer height with a margin */
var st = $(window).scrollTop();
var sb = $(".loginform");
var sbi = $(".loginform #loginform");
var sb_ot = sb.offset().top;
var sbi_ot = sbi.offset().top;
var sb_h = sb.height();

if(sb_h + $(document).scrollTop() + sb_m + mb < $(document).height()) {
    if(st > sb_ot) {
        var h = Math.round(st - sb_ot) + sb_m;
        sb.css({"paddingTop" : h});
    }
    else {
        sb.css({"paddingTop" : 0});
    }
}
});

on bare HTML everything works fine.
if add a script to theme an endless scroll appears
here can see bug
this behavior occurs if add a widget to footer
please tell me what is problem?

• This topic was modified 3 years, 3 months ago by milatovskaja.

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