How to make adding a comment a step in the moving to Blocked transition?

[Melanie Beaudry Desjardins]

I've added a 'Field has been modified Validator' for the comment field in my transition to the Blocked status. However, that doesn't give the user the opportunity to add a comment during the transition. It simply denies the transition and shows the error message. 

How do I introduce the step to add a comment during the transition so the validation is successful?

[Nic Brough -Adaptavist-]

The transition between the two status needs to have a "transition screen" set.  The screen doesn't need to have any fields on it, if the user has comment permission, the comment box will appear there and let them enter a new comment.

[Melanie Beaudry Desjardins]

I do, at this point I've figured out that I'll need to create a screen scheme specific to the project where this change applies because the Blocked status is shared across multiple projects (teams). I haven't figure out how to add a screen to a transition and I'm wondering if it's because I have the workflow set to ALL statuses can move to Blocked? I'm not seeing an option to allocate a screen to the transition from ALL to Blocked.

[elizabeth_jones]

Hi @Melanie Beaudry Desjardins do you have permissions to modify the project workflow?