Websites loading from app.local.gist.build

Questions

Which websites load from app.local.gist.build?

The 33 sites listed on this page. A site is listed when its stored HTML has a script, iframe or stylesheet from the host, or one of its own scripts names the host in an absolute URL.

Is app.local.gist.build a third party for every site listed?

Yes: a host under a site's own registrable domain is never recorded for that site, so every site here loads from app.local.gist.build as a dependency outside its own domain.