raster conversion - Error running r.thin in QGIS

I get the following error when running r.thin:

Traceback (most recent call last): File "C:/PROGRA~4/QGIS3/apps/qgis/./python/plugins\processing\algs\grass7\Grass7Algorithm.py", line 395, in processAlgorithm outputs[outName] = parameters[outName] NameError: name 'QgsProcessingOutputHtml' is not defined

Execution failed after 5.26 seconds

I looked at the Python script containing that section of code:

# Return outputs map
        outputs = {}
        for out in self.outputDefinitions():
            outName = out.name()
            if outName in parameters:
                outputs[outName] = parameters[outName]
                if isinstance(out, QgsProcessingOutputHtml):
                    self.convertToHtml(parameters[outName])


        return outputs

Thinking that a function wasn't called to start with, I added this to the call for the function:

from qgis.core import (Qgis,
                       QgsRasterLayer,
                       QgsApplication,
                       QgsMapLayer,
                       QgsProcessingUtils,
                       QgsProcessing,

                       QgsMessageLog,
                       QgsVectorFileWriter,
                       QgsProcessingAlgorithm,
                       QgsProcessingParameterDefinition,
                       QgsProcessingException,
                       QgsProcessingOutputHtml,

I still get the error. Is this a missing function, or is does this function exist anymore? I loaded the latest QGIS version (3.0.1).