mobile

After updating to 5.0 earlier today, I noticed that it added the action button to the default messenger app (among others), however, it doesn't seem to have added it to Hangouts. Is there a reason it's not in that app? Does the Nexus 6 have it in Hangouts? I'm just generally confused as to why it's in Gmail and not Hangouts.

Any insight would be greatly appreciated, thanks!