We have created multiple forms and it contains many dropdown select widgets. We want user to navigate through the form fields using the "tab" but the dropdown select is getting skipped.

Tab index is not working when we add that in the advance format for the dropdown select widget as well as in the input widget extended properties which is mapped to the dropdown select.

Below are examples for errors that we are facing when we add the tabindex in the advanced format of the dropdown widget-

VM7086:3 Uncaught SyntaxError: Unexpected token ':'
    at start (DropdownSelect.en.js?32132:27:58)
    at Object.init (DropdownSelect.en.js?32132:169:13)
at HTMLDocument.dropdownSelectDOMReadyHandler (**********)

The configuration that we are adding in advanced format is

"

""tabindex"":5

"