Hi Johnny,

You can see more about startup events here:

https://our.umbraco.com/documentation/reference/events/application-startup

To update a media property you want to use IMediaTypeService and IDataTypeService which you can add to your class using Dependency Injection.

Once you have access to IMediaTypeService and IDataTypeService you can update the properties of a media type using:

    var imageType = _mediaTypeService.Get("Image");

    if (imageType != null)
    {
       //Add true false datatype
       var trueFalseDataType = _dataTypeService.GetDataType("True/false");
       PropertyType myProperty = new PropertyType(trueFalseDataType ,"myProperty");
       myProperty.Name = "My true false property";
       imageType.AddPropertyType(myProperty , "Image");
      _mediaTypeService.Save(imageType );
    }

Thanks Marc,

Works accordingly

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