A new version has been released that includes support for the soon to be changed configuration options for Fan and Thermostat devices
Users can now start adjusting their setup to use the new configuration options:
Thermostat
:modes
has been renamed tothermostatModes
Fan
:speeds
has been renamed tofanSpeeds
Until the rollout of v4 both options should work, but I advice everyone to already adjust their setup.
Next to that I moved the migration guide to a new place: Migration Guide · openhab/openhab-google-assistant · Discussion #558 · GitHub
Please check your item types according to the attached list.