FlaskRedis.init_app method no longer takesstrict parameter. Pass this flag when creating your FlaskRedis'REDIS', so unless you change that, you can still access the extension viaapp.extensions['redis'] as before.redis.StrictRedis. You can switch back to the old redis.Redis class bystrict=False in the FlaskRedis kwargs.Redis keyword arguments (such asdecode_responses) to FlaskRedis and they will be correctly passed overredis-py instance. Thanks, @giyyapan!redis_store['key'] = value, redis_store['key'], anddel redis_store['key'] is now supported. Thanks, @ariscn!