Tabindex does not work

[svivian]

Describe the bug
The tabindex attribute on elements is ignored.

To Reproduce
Example HTML, with the select element being enhanced by Choices.js:

<input type="text" tabindex="1">
<select tabindex="2">
  <option>Example</option>
</select>
<input type="text" tabindex="3">

Expected behavior
Pressing tab should go from the text input to the dropdown then the second text input. However it skips all elements enhanced by Choices.js. The outer div (class="choices") has tabindex="0" while the inner select element has tabindex="-1" (the latter is expected as the original select shouldn't be focusable).

The tab index should be copied across to the Choices element.

Choices version and bundle

• Version: 11.0.2

Desktop (please complete the following information):

• OS: MacOS
• Browser Chrome, Firefox (latest)