https://www.bleepingcomputer.com/news/security/apple-to-fix-ios-bug-granting-full-access-to-3rd-party-keyboards/

After releasing iOS 13.1 to fix a long list of bugs left unpatched in iOS 13, Apple says in a support document published today that an issue is impacting third-party iOS 13 and iPadOS keyboard extensions.

iOS third-party keyboard extensions are apps designed to run either entirely standalone, without requiring access to any external services, or with "full access" for additional features that need network access.