Quick write up on extracting a GraphQL schema when introspection is disabled. Bits and pieces sourced from various sources. Successfully tested on an Apollo instance.
TLDR: Some GraphQL instances provide name autocomplete suggestions. Some peeps have written tools to automate the extraction process. (ref https://youtu.be/nPB8o0cSnvM).
First step is using a tool called clairvoyance by @nikitastupin (https://github.com/nikitastupin/clairvoyance). I found the main repo to lack error handling and support for additional features such as proxy.