> if we are using non-responsive 3rd party templates our sites will not be responsive. correct?
You are correct, If 3rd-party template isn't responsive, the site will not be responsive as well. If you want your site to be responsive you need to get responsive template.
> what exactly is the "new confirmation popup" all about?
We get rid of build-in into browser JS confirmation popup, instead we used custom popup for this purpose.
> I assume since they weren't mentioned, see more no upgrades to the functionality of the mobile apps was included in 7.2. correct?
You are correct. Mobile apps stays intact. However we are planning to update them later.
You are correct, If 3rd-party template isn't responsive, the site will not be responsive as well. If you want your site to be responsive you need to get responsive template.
> what exactly is the "new confirmation popup" all about?
We get rid of build-in into browser JS confirmation popup, instead we used custom popup for this purpose.
> I assume since they weren't mentioned, see more