Why doesn't mouseleave and mouseout work with bootstrap tab show event on Chrome?

Question

I have been working on customizing this bootstrap responsive tabs example. What I wanted was to cycle the tabs like a slider when user hovers over left/right arrow icon. Along with that I also wanted the slider to keep cycling if the user keeps hovering over left/right arrow icon. I wrote following code for that:

(function() {


  function changeTab() {

    console.log("mouseenterd on ", $(this));

    if ($(this).closest("li").hasClass("next") && !$(this).closest("li").hasClass("hovered")) {
      $(this).closest(".nav-tabs").children("li").removeClass("hovered");
      $(this).tab('show');
    } else if ($(this).closest("li").hasClass("prev") && !$(this).closest("li").hasClass("hovered")) {
      $(this).closest(".nav-tabs").children("li").removeClass("hovered");
      $(this).tab('show');
    }
  }

  function outOfHover() {

    console.log("mouseleave on ", $(this));

    if ($(this).closest("li").hasClass("hovered")) {
      $(this).closest(".nav-tabs").children("li").removeClass("hovered");
    }

  }




  $('[data-toggle="tab"], [data-toggle="pill"]').on('mouseleave', outOfHover); //removes class hovered
  $('[data-toggle="tab"], [data-toggle="pill"]').on('mouseenter', changeTab); //runs bootstrap tabs like slider

  var triggerClickTab;
  var triggerClickCarousel;

  function triggerClick(that) {
    $(that).tab('show');
    console.log("show triggered " + " ", $(that));
  }

  $('[data-toggle="tab"], [data-toggle="pill"]').on('mouseenter', function() {
    var that = this;
    triggerClickTab = setInterval(triggerClick, 1650, that);
  });

  $('[data-toggle="tab"], [data-toggle="pill"]').on('mouseleave', function() {
    clearInterval(triggerClickTab);
  });



  $("#myCarousel .carousel-control").on('mouseenter', function() {

    if ($(this).hasClass("left")) {
      $("#myCarousel").carousel('prev');
    } else if ($(this).hasClass("right")) {
      $("#myCarousel").carousel('next');
    }

    var that = this;
    triggerClickCarousel = setInterval(triggerClick, 1650, that);
  });

  $("#myCarousel .carousel-control").on('click', function() {

    clearInterval(triggerClickCarousel);

    var that = this;
    triggerClickCarousel = setInterval(triggerClick, 1650, that)
  });

  $("#myCarousel .carousel-control").on('mouseleave', function() {
    clearInterval(triggerClickCarousel);
  });

  /* end if Condition for non-touch device finsihes here */

  $(document).on('show.bs.tab', '.nav-tabs [data-toggle="pill"], .nav-tabs [data-toggle="tab"]', function(e) {
    var $target = $(e.target);
    var $tabs = $target.closest('.nav-tabs');
    var $current = $target.closest('li');
    var $parent = $current.closest('li.dropdown');
    $current = $parent.length > 0 ? $parent : $current;
    var $next = $current.next();
    var $prev = $current.prev();

    var updateDropdownMenu = function($el, position) {
      $el
        .find('.dropdown-menu')
        .removeClass('pull-left pull-center pull-right')
        .addClass('pull-' + position);
    };

    $tabs.find('>li').removeClass('hovered');

    if ($current.hasClass("next")) {
      $next.addClass('hovered');

    } else if ($current.hasClass("prev")) {
      $prev.addClass('hovered');
    }

    $tabs.find('>li').removeClass('next prev');
    $prev.addClass('prev');
    $next.addClass('next');

    updateDropdownMenu($prev, 'left');
    updateDropdownMenu($current, 'center');
    updateDropdownMenu($next, 'right');
  });



}());

/**
 * Responsive Bootstrap Tabs by @hayatbiralem
 * 15 May 2015
 */

@media screen and (max-width: 479px) {
  .nav-tabs-responsive > li {
    display: none;
    width: 23%;
  }
  .nav-tabs-responsive > li > a {
    max-width: 100%;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    word-wrap: normal;
    width: 100%;
    width: 100%;
    text-align: center;
    vertical-align: top;
  }
  .nav-tabs-responsive > li.active {
    width: 54%;
  }
  .nav-tabs-responsive > li.active:first-child {
    margin-left: 23%;
  }
  .nav-tabs-responsive > li.active,
  .nav-tabs-responsive > li.prev,
  .nav-tabs-responsive > li.next {
    display: block;
  }
  .nav-tabs-responsive > li.prev,
  .nav-tabs-responsive > li.next {
    -webkit-transform: scale(0.9);
    transform: scale(0.9);
  }
  .nav-tabs-responsive > li.next > a,
  .nav-tabs-responsive > li.prev > a {
    -webkit-transition: none;
    transition: none;
  }
  .nav-tabs-responsive > li.next > a .text,
  .nav-tabs-responsive > li.prev > a .text {
    display: none;
  }
  .nav-tabs-responsive > li.next > a:after,
  .nav-tabs-responsive > li.next > a:after,
  .nav-tabs-responsive > li.prev > a:after,
  .nav-tabs-responsive > li.prev > a:after {
    position: relative;
    top: 1px;
    display: inline-block;
    font-family: 'Glyphicons Halflings';
    font-style: normal;
    font-weight: 400;
    line-height: 1;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
  }
  .nav-tabs-responsive > li.prev > a:after {
    content: "\e079";
  }
  .nav-tabs-responsive > li.next > a:after {
    content: "\e080";
  }
  .nav-tabs-responsive > li.dropdown > a > .caret {
    display: none;
  }
  .nav-tabs-responsive > li.dropdown > a:after {
    content: "\e114";
  }
  .nav-tabs-responsive > li.dropdown.active > a:after {
    display: none;
  }
  .nav-tabs-responsive > li.dropdown.active > a > .caret {
    display: inline-block;
  }
  .nav-tabs-responsive > li.dropdown .dropdown-menu.pull-xs-left {
    left: 0;
    right: auto;
  }
  .nav-tabs-responsive > li.dropdown .dropdown-menu.pull-xs-center {
    right: auto;
    left: 50%;
    -webkit-transform: translateX(-50%);
    -moz-transform: translateX(-50%);
    -ms-transform: translateX(-50%);
    -o-transform: translateX(-50%);
    transform: translateX(-50%);
  }
  .nav-tabs-responsive > li.dropdown .dropdown-menu.pull-xs-right {
    left: auto;
    right: 0;
  }
}
/**
 * Demo Styles
 */

.wrapper {
  padding: 15px 0;
}
.bs-example-tabs .nav-tabs {
  margin-bottom: 15px;
}
@media (max-width: 479px) {
  #narrow-browser-alert {
    display: none;
  }
}

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js" integrity="sha384-Tc5IQib027qvyjSMfHjOMaLkfuWVxZxUPnCJA7l2mCWNIpG9mGCD8wGNIcPD7Txa" crossorigin="anonymous"></script>
<div class="wrapper">
  <div class="container">
    <div id="narrow-browser-alert" class="alert alert-info text-center">
      <strong>Heads up!</strong>
      <br>Narrow your browser!</div>
    <div class="bs-example bs-example-tabs" role="tabpanel" data-example-id="togglable-tabs">
      <ul id="myTab" class="nav nav-tabs nav-tabs-responsive" role="tablist">
        <li role="presentation" class="active">
          <a href="#home" id="home-tab" role="tab" data-toggle="tab" aria-controls="home" aria-expanded="true">
            <span class="text">Home</span>
          </a>
        </li>
        <li role="presentation" class="next">
          <a href="#profile" role="tab" id="profile-tab" data-toggle="tab" aria-controls="profile">
            <span class="text">Profile</span>
          </a>
        </li>
        <li role="presentation">
          <a href="#samsa" role="tab" id="samsa-tab" data-toggle="tab" aria-controls="samsa">
            <span class="text">Metamorfoz by Franz Kafka</span>
          </a>
        </li>
        <li role="presentation">
          <a href="#samsa2" role="tab" id="samsa-tab" data-toggle="tab" aria-controls="samsa">
            <span class="text">Nup</span>
          </a>
        </li>
        <li role="presentation">
          <a href="#samsa3" role="tab" id="samsa-tab" data-toggle="tab" aria-controls="samsa">
            <span class="text">haha lol</span>
          </a>
        </li>
      </ul>
      <div id="myTabContent" class="tab-content">
        <div role="tabpanel" class="tab-pane fade in active" id="home" aria-labelledby="home-tab">
          <p>
            Raw denim you probably haven't heard of them jean shorts Austin. Nesciunt tofu stumptown aliqua, retro synth master cleanse. Mustache cliche tempor, williamsburg carles vegan helvetica. Reprehenderit butcher retro keffiyeh dreamcatcher synth. Cosby sweater
            eu banh mi, qui irure terry richardson ex squid. Aliquip placeat salvia cillum iphone. Seitan aliquip quis cardigan american apparel, butcher voluptate nisi qui.
          </p>
        </div>
        <div role="tabpanel" class="tab-pane fade" id="profile" aria-labelledby="profile-tab">
          <p>
            Food truck fixie locavore, accusamus mcsweeney's marfa nulla single-origin coffee squid. Exercitation +1 labore velit, blog sartorial PBR leggings next level wes anderson artisan four loko farm-to-table craft beer twee. Qui photo booth letterpress, commodo
            enim craft beer mlkshk aliquip jean shorts ullamco ad vinyl cillum PBR. Homo nostrud organic, assumenda labore aesthetic magna delectus mollit. Keytar helvetica VHS salvia yr, vero magna velit sapiente labore stumptown. Vegan fanny pack odio
            cillum wes anderson 8-bit, sustainable jean shorts beard ut DIY ethical culpa terry richardson biodiesel. Art party scenester stumptown, tumblr butcher vero sint qui sapiente accusamus tattooed echo park.
          </p>
        </div>

        <div role="tabpanel" class="tab-pane fade" id="samsa" aria-labelledby="samsa-tab">
          <p>
            One morning, when Gregor Samsa woke from troubled dreams, he found himself transformed in his bed into a horrible vermin.
          </p>
          <p>
            He lay on his armour-like back, and if he lifted his head a little he could see his brown belly, slightly domed and divided by arches into stiff sections.
          </p>
        </div>
        <div role="tabpanel" class="tab-pane fade" id="samsa2" aria-labelledby="samsa-tab">
          <p>
            He lay on his armour-like back, and if he lifted his head a little he could see his brown belly, slightly domed and divided by arches into stiff sections.
          </p>
        </div>
        <div role="tabpanel" class="tab-pane fade" id="samsa3" aria-labelledby="samsa-tab">
          <p>
            One morning, when Gregor Samsa woke from troubled dreams, he found himself transformed in his bed into a horrible vermin.
          </p>
          <p>
            He lay on his armour-like back, and if he lifted his head a little he could see his brown belly, slightly domed and divided by arches into stiff sections.
          </p>
        </div>
      </div>
    </div>
  </div>
</div>

The code doesn't work properly on stackoverflow becasue of media queries. Please try this filddle which has exactly same code and works fine: https://jsfiddle.net/hhtm1on3/ Plz narrow the width of output untill you see left/right arrowed version of tabs.

The jsfiddle code works correct in firefox browser but not in chrome browser. I have added comments in console when particular events are fired. As you can see on firefox mouseleave keeps firing after every tab is shown but not chrome. The same happens with mouseout event.

Question:

1. Why doesn't mouseleave and mouseout work with bootstrap tab show event on Chrome?
2. What is the workaround to this?

Answer 1

Chrome is known to not handled some mouse event if the cursor doesn't move. Something to do with UI repaint optimization.

One workaround could be to force on each interval callback an UI redraw.There is many ways to force a redrawn, one is to repaint element itself, e.g:

function triggerClick(that) {                    
    $(that).tab('show').hide().show(0); // force a repaint
    console.log("show triggered " + " ", $(that));
}

See: -updated jsFiddle-

Answer 2

I am not sure what influence this has on the bug's priority level for -WebKit please read this WebKit Bugzilla you can find this bug check this link Click here