For a few weeks now Facebook won't upload photos. I'm trying to upload photos that are sitting on my desktop -- they're in png format. This seems limited to Safari. I can upload from Chrome. And I don't have problems with my iOS devices uploading. Attached are a picture indicating what happens if I try to upload a photo to a new post -- white circle on grey box, nothing happens: if I click away it says it's still loading, but it never does. Also a picture which shows what happens when I try to add a photo to a comment on an existing post.