Cannot edit post with additional properties being added to schema

Hello there,

I have a self-hosted Ghost CMS with modifications to the source code, and I run into an issue of being unable to save a post due to having an additional property compared to the original schema.

I get this:
{“errors”:[{“message”:“Validation error, cannot edit post.”,“context”:“Validation failed for posts[0].”,“type”:“ValidationError”,“details”:[{“keyword”:“additionalProperties”,“dataPath”:".posts[0]",“schemaPath”:"#/additionalProperties",“params”:{“additionalProperty”:“feature_vector_image”},“message”:“should NOT have additional properties”}],“property”:“posts[0]”,“help”:null,“code”:null,“id”:“d9f6f540-61b8-11ec-9e4f-13e5cb1888b2”}]}

How can I enable Ghost to handle additional properties?