Can't find background for subtitles

[Pamela22218841y5i3]

My essential Graphics sidebar is not showing options to add or change a background for the subtitles. It only shows appearance Fill and Background, and the background option doesn't seem to do anything.  These are CC708 closed captions, is that the reason?

 

[Stan Jones]

Yes, you are seeing limited options because you have a 708 Closed Caption track.

But the reason you are not seeing the Black background you have selected is that, like closed captions in the past, there are actually 2 settings in the one dropdown. You probably have "Transparent" set. Change it to "Opaque" or "Translucent."

Stan