Will fuss at you for 60s if you are a balance druid, cast a variety of offensive spells, have the Moonkin Form talent, and aren't in Moonkin Form.
If you mount up after combat, it will pop up. I added a blacklist for flight form and swift flight form, but if you would like to add your other mount(s), add the spell id numbers to Trigger 7 (see the second image).
You can find the spellid of your mount using a spellid WA or addon or by looking the mount up in wowhead. For example, great white kodo: https://www.wowhead.com/wotlk/spell=23247/great-white-kodo