Extra links supported for operators coming from third-party packages:

airflow.serialization.serialized_objects.BUILTIN_OPERATOR_EXTRA_LINKS

airflow/providers_manager.py
"""
    Manages all provider packages. This is a Singleton class. The first time it is
    instantiated, it discovers all available providers in installed packages and
    local source folders (if airflow is run from sources).
    """
    _instance = None
    resource_version = "0"
    def __new__(cls):
        if cls._instance is None:
            cls._instance = super().__new__(cls)
        return cls._instance
    def __init__(self):
        
        self._provider_dict: Dict[str, Tuple[str, Dict]] = {}
        
        
        self._hooks_dict: Dict[str, Tuple[str, str]] = {}
        self._validator = _create_validator()
        
        
        
        
        self._discover_all_airflow_builtin_providers_from_local_sources()
        self._discover_all_providers_from_packages()
        self._discover_hooks()
        self._provider_dict = OrderedDict(sorted(self.providers.items()))
        self._hooks_dict = OrderedDict(sorted(self.hooks.items()))
    def _discover_all_providers_from_packages(self) -> None: