When I click on the person's name in the person page I get sources not the "Person side sheet".
@ECameron27 Could you please clarify where you are clicking on a person's name? It would be most helpful if you included a URL (web address) for the page you are viewing when you click on a person's name, as well as the specific name you are clicking on.
When I am on the Details tab of a person page (such as https://www.familysearch.org/tree/person/details/LZTB-DMS) and I click on a person's name, I get the person card popup. There are many other places you might be able to click on a person's name, so it would be helpful to get some more specifics.