I'm leveling a druid and the covenant ability does not disappear when I drag it to my action bars, but only in cat or cat/stealth forms.
My ElvUI is up to date. And the Zone ability button doesn't show in other forms. Screenshot with everything but ElvUI and ElvUI plugins enabled and a screen shot with only ElvUI and ElvUI options enabled. https://imgur.com/a/szEk2EF