[Plugin: User Role Editor] Can't see read_hidden_forums

I have hidden bbpress forums that I want my Participants to be able to see. I’ve looked all over and everything says I should be able to check read_hidden_forums to give them this permission, using the User Role Editor plugin. But I don’t have that capability available for me to turn on or off. I’ve tried adding the capability and it says it already exists. But looking at my core capabilities and custom capabilities, it’s not there.

I took a screenshot of the capabilities I do have here: https://screencast.com/t/RpenUvVx