Removed:

• script_info is no longer passed as the first arg / matching kwarg to an app factory function. It is no longer passed as the first arg to many internal CLI functions.
• config.from_json, use config.from_file(path, json.load) instead.
• json functions no longer take an encoding parameter.
• safe_join, use werkzeug.utils.safe_join instead.
• total_seconds, use timedelta.total_seconds instead.
• The same blueprint can't be registered with the same name, every registration requires a unique, possibly nested, name.

Some parameters to send_file and send_from_directory were renamed to be more accurate to what they did when moving the implementations to Werkzeug. These old names were deprecated in Flask's wrappers. The deprecation period has been extended to 2.2. attachment_filename is renamed to download_name, cache_timeout is renamed to max_age, add_etags is renamed to etag, and filename is renamed to path.