On recent Home Assistant versions, opening the integration options causes:
Config flow could not be loaded: 500 Internal Server Error
Traceback:
AttributeError: property 'config_entry' of 'OptionsFlowHandler' object has no setter
Root cause:
In config_flow.py, OptionsFlowHandler.init assigns:
self.config_entry = config_entry
But config_entry is now a read-only property in HA.
Workaround / fix:
Rename the attribute, e.g.
self._config_entry = config_entry
and update references accordingly.
Integration works otherwise; only the options/config UI crashes.
HAOS, HA Core Version