tabIndex backwards not working with clear button

[RobinAraCom]

Describe the bug
when you have the dropdown in focus and press tab, you get to the clear button as expected.
when you press shift + tab you get back to the dropdown as expected.
when you press shift + tab (from the dropdown) you are supposed to get to the previous input, but you get to the clear button (the next elemet).

Reproducbile example
live demo, probably everywhere work for me on the first dropdown I saw.

more info
when you spam shift + tab it toggels between the dropdown and the clear button. Even tho there are alot of other inputs on the page.

[lssbq]

Same issue encounted, it trapped the focus and prevent user navigate back by keyboard.
I can only focus backward by 'shift + tab' on the dropdown panel opened.

[RobinAraCom]

SHIFT + Tab will also select the entry when [selectOnTab] is true, which I think is not desired. Not sure if I should open an new Issue for this.

@lssbq thank you very much for the screenshot/gif

[oliverguenther]

I opened a pull request for this issue, allowing shift+tab to escape the ng-select with the clear icon shown: #2371