For some reason the extractors that i place on an automatic farm have stopped extracting from the chests when they used to work.

I haven't followed this mod that far back, but in the newer versions, you have to use a portable storage interface on the contraption, and a transposer on the ground.

Extractors are also supposed to work as can be seen in the "Moving Block Contraptions in Create 0.2" video (at about 20 minutes) made by Simi Cats, the same account that posted the "This is Create" trailer.

I don't think that was ever shown, what you see there is the portable storage interface.
https://youtu.be/hKJxlkeEZ8M?t=1438

edit: Extractors are used in the video, but for throwing items into the world, not into any kind of storage.

Exactly, that's what isn't working

I apologize, I totally misread your message, i read into chests.

Did this happen after an update, or all of the sudden? I would also have a few other questions that would probably be answered if you could post a short video of this occuring (< 10s would be enough).

Again sorry for the misunderstanding!

No worries on the misunderstanding. As for when it happened I would guess it was after an update because the farm produces fairly slowly and the chests were pretty full when i finally noticed (this is in a creative test world so i wasn't actually using it in a way that I would notice problems quickly). I'd be willing to post a video but i'm not sure how. I tried when I opened the issue but it said the file type wasn't supported.

Actually no need, this is a duplicate of #317, I just never noticed it cause Snownee (the person that posted the bug) closed it so quick.. so this is why devs often don't close issues until when a version including that fix is released.
Next version will have this fixed! :)

Alright thanks.