Making transitions conditional upon other elements - not working

Problem/Motivation

Under 'Conditions' for a workflow element, you can select as the "State" a 'disable {transition} transition'.

This should in theory disable that transition in the transition dropdown box when that condition is met. Currently this does not work.

Steps to reproduce

Add a condition to disable a transition based on another element. Nothing happens.

e.g. this should disable 'Query with customer' when the e-mail address has a value.

  '#states':
    disable_transition-query_with_customer:
      ':input[name="your_e_mail_address"]':
        filled: true

Proposed resolution

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Remaining tasks

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