I voted to close this question "How can I fix this QGIS error?" as off-topic - submission of bug reports etc - but am having second thoughts as the GitHub repository seems to indicate that the plugin has been abandoned as issues are not being addressed and no commits have been made for a few years.
As issues/bug reports aren't being addressed, it seems a little wrong to close it when there's no avenue to report the bug for resolution and the GIS-SE community can actually assist.
I'm going to nominate for re-opening and let the community decide, but am interested in a general meta position.
Should bugs/issues with abandoned software be closed as off topic, particularly where GIS-SE can actually assist?