It maybe it's a problem in custom template, please try to switch to some of UNA Templates to see if the problem goes away ?
It's in every single template now after new upgrade and as you can see I haven't added any submenus
So this was in "All Feeds Outline" and "All Feeds Timeline". These are the blocks that are supposed to let you switch between Feed, Public, and Hot but thats not available now after upgrade.
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