Modal tabs into background when last tabbable's tabindex="-1"

[antman888]

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Bug description: When the last tabbable element in a modal has tabindex="-1", tabbing does not return focus to the first element in the modal. It puts focus onto the background elements.

Link to minimally-working plunker that reproduces the issue: http://plnkr.co/edit/ejYEeIrDul5vrX9twvre?p=preview

Version of Angular, UIBS, and Bootstrap

Angular:

UIBS:

Bootstrap:

[antman888]

A possible solution is to filter elements with a tabindex="-1" attribute.

var tabbableSelector = 'a[href], area[href], input:not([disabled]):not([tabindex=\'-1\']), ' +
        'button:not([disabled]):not([tabindex=\'-1\']),select:not([disabled]):not([tabindex=\'-1\']), textarea:not([disabled]):not([tabindex=\'-1\']), ' +
        'iframe, object, embed, *[tabindex]:not([tabindex=\'-1\']), *[contenteditable=true]';

[wesleycho]

Sounds legitimate - feel free to file a PR