The Typescript definitions for Kendo UI define the kendo.ui.ToolBarOpenEvent as follows:

interface ToolBarEvent {
        sender: ToolBar;
        preventDefault: Function;
        isDefaultPrevented(): boolean;
}

interface ToolBarOpenEvent extends ToolBarEvent {
        SplitButton?: JQuery | undefined;
}

The event is also documented that way in https://docs.telerik.com/kendo-ui/api/javascript/ui/toolbar/events/open. However, the corrersponding method in kendo-toolbar.js:446-453 does the following:

open: function (e) {
    var isDefaultPrevented = that.toolbar.trigger(OPEN, { target: element });
    if (isDefaultPrevented) {
        e.preventDefault();
        return;
    }
    that.adjustPopupWidth(e.sender);
},

The documentation at  https://docs.telerik.com/kendo-ui/api/javascript/ui/toolbar/configuration/items.menubuttons does not mention the children of a splitButton can have their own click handlers. It's not present in the typings either.

However, this does work: https://dojo.telerik.com/@GaloisGirl/UYeBewEX

Somewhat related is this bug: https://github.com/telerik/kendo-ui-core/issues/4542  . Documenting the behavior would be useful in accurately describing this bug.

I tested the toolbar example https://demos.telerik.com/kendo-ui/toolbar/keyboard-navigation with a keyboard and screen reader (NVDA) and found the following issues:

1. Buttons are rendered as links. The SR announces the first button as "Button visited link". Apparently, there is an undocumented option useButtonTag (https://github.com/telerik/kendo-ui-core/issues/4730) that's also missing from the typings. I have to manually add 'role: "button"' to every single button to make my toolbar compliant.

2. Toggle buttons state is not announced.
 
3. The overflow menu button has no caption and is announced by the SR as "blank".

4. The overflow menu button has no visible focus styling (screenshot attached).

5. Selecting an item from the overflow menu throws the focus out of the page.

Describe the bug
In IE11 on resizing horizontally the browser window, the text of the ToolBar's tools overlaps.

To reproduce
Steps to reproduce the behavior:

1. Open: dojo example in IE11.
2. Resize the browser window making it narrower.

The tools size is not properly calculated and text overlapping can be observed (see the screenshot linked below). Overflow hidden is not set to the button tool and the k-input elements are resized on resizing the browser window.

The following CSS rule can be used as a workaround:

.k-toolbar .k-button,
.k-toolbar .k-input {
  overflow: hidden;
  flex: 0 0 auto;
}

Expected behavior
The ToolBar tools should properly resize on browser window resize. No text overlapping should occur.

Screenshots
Screenshot.

Affected package (please provide)

• theme-default
• theme-bootstrap
• theme-material

Affected suites (please provide)

• Kendo UI for jQuery

Affected browsers (please provide)

• IE version: 11

Build system information (please provide)

• OS: Windows
• Node version: N/A
• NPM version: N/A

Additional context
N/A

Toolbar's show() and hide() method do not properly toggle items visibility in the overflow popup.

Case 1: https://dojo.telerik.com/aXEyIrEW/6

The 'Button' is visible in both the Toolbar and the overflow popup initially.

Case 2: https://dojo.telerik.com/erEnafir/39

When the Toolbar is resized so that the 'Dashboard' button is not visible, the 'Dashboard' button is also not visible in the overflow popup.