Before I share my answer, I will say that info save automatically if you're logged in. If you are logged in, then click the "Hide" text if it's there. Now, you should see black text saying "All changes saved." But if you are logged in and don't see the "Save" button, try refreshing the page. Also, if you see red text saying “Changes not saved” while your editing a person on the tree, keep editing it. It goes away once you press “Ok”.