This issue was found while using vaadin-dialog.
The dialog component uses IronFocusablesHelper.getTabbableNodes to trap tab selection to the element inside of it when opened. We found out that in IE11, one of the examples wasn't preventing the selection to go outside of the dialog.
It turns out that the reason for that was that the dialog has one SVGElement inside of it.
Description
This issue was found while using
vaadin-dialog
. The dialog component usesIronFocusablesHelper.getTabbableNodes
to trap tab selection to the element inside of it when opened. We found out that in IE11, one of the examples wasn't preventing the selection to go outside of the dialog.It turns out that the reason for that was that the dialog has one
SVGElement
inside of it.On IE11,
SVGElement#children
returnsundefined
instead of an emptyHTMLCollection
, so on this line https://github.com/PolymerElements/iron-overlay-behavior/blob/master/iron-focusables-helper.html#L136,children.length
fails with"Unable to get property 'length' of undefined or null reference"
.Expected outcome
Focusable elements are returned on IE11.
Actual outcome
Error is thrown and no execution is stopped.
Example Project
iron-focusables-issue.zip
Steps to reproduce
Print focusable items
button on top of the page.