Conditional Tags pod does not appear

Hi, all.

I am working in FrameMaker 2015 in Windows 10.

The Conditional Tags pod has mysteriously disappeared. When I select text and select Special/Conditional tags, nothing happens. When I select View/Pods/Conditional Tags, nothing happens. Either way, I can't display the pod that allows me to select a condition and apply it.

The files I am working in do contain conditional text, which has been successfully applied in the past. The Show/Hide Conditional Text pod lists all four conditions that my documents contain. I've selected Show Condition Indicators, and the text that has had conditions applied is being displayed correctly.

I vaguely recall this happening once before. What is going on?

Thanks.