Custom Features for FeatureExtractor

[koaning]

When I look at the settings for the FeatureExtractor I see an example config listed.

[model]
@architectures = "spacy.FeatureExtractor.v1"
columns = ["NORM", "PREFIX", "SUFFIX", "SHAPE", "ORTH"]

It seems to encode features that are attached to Token objects. What if I'd like to add my own features to the mix here? It's recommended to add features using an extension. Is it also possible to refer to features here that were added from an extension?

[adrianeboyd]

Sure, with a custom feature extractor. Here's a user's example: #6527 (comment)