Squares should not be tab-able when matched or answered

[uriklar]

In Square.tsx you have the Container component which has tabIndex: 0;
This makes squares accessible by tabbing. But, once the itemState is either AnswerState.Matched or AnswerState.Answered
there's no reason for them to be tab-able since the user can't interact with them.

You can make Containers attrs dynamic by having it accept props. Something like:

.attrs( props => ({ role: "button", tabIndex: props.isTabbable ? 0 : 1}))

Now, when a category is found or answered, pressing tab should skip it.