jira - custom fields that were single-select lists have gone blank

[Varsha Mungale]

Hi,

I have custom fields that are single-single lists. Has there been a change recently? I am unable to see the options. How do i select one of the values? 
The text-box/single-select selection box is present on the ticket but it is not visible. I have to click on the space to the right of the field-label and the selection box shows-up. Where to click so that the box shows up is a little mysterious.

[Yogesh Mude]

@Varsha Mungale  Not getting you what exactly the issue it is. It would be good if you can share the snap.

[Varsha Mungale]

This is the "Reviewer" field 

To the right side, it is blank space. 

I have to scroll to the right and click in various places to see this 

This change is recent. Earlier this option was visible by default. 

This non-visibility of options field is confusing the users