bootstrap modal disappear immediately after showing

In my case the problem of showing and immediately disappearing modal window was that I called toggle twice. First, in tag in HTML file, and then when attaching event handler in JavaScript file, like so:

<a role="menuitem" tabindex="-1" href="#" data-toggle="modal" data-target="#myModal" id="deleteItemButton">Delete Item</a>

$ultodoListDisplay.on( "click", "#deleteItemButton",  function(){
    $('#myModal').modal('toggle');
});

References to the Bootstrap CDN and stylesheets were correct. Therefore, define toggle of modal window only once.

I had this problem and the solution was simple... I was loading both bootstrap.js AND bootstrap-modal.js.

bootstrap.js includes bootstrap-modal.js.

Solution: Remove bootstrap-modal.js from your head and it'll work correctly.