A comrade responded with a few in a post I made asking something similar. https://lemmygrad.ml/post/2415616

https://github.com/mendel5/alternative-front-ends#readme

https://anonigviewer.com

https://imgsed.com

There is Bibliogram (now mostly defunct, the dev has abandoned it) and Proxigram for Instagram.

I am unaware of any Facebook frontends if they exist.