I think that this may be some duplicate extension trying to generate and take advantage of user confusion between the real Dark Reader extension for Edge and this one.

Real Dark Reader:

https://microsoftedge.microsoft.com/addons/detail/dark-reader/ifoakfbpdcdoeenechcleahebpibofpc

What appears to be the copycat with the malware:

https://microsoftedge.microsoft.com/addons/detail/dark-reader-%E2%80%93-ultimate-da/lgjebhldhklllbkkbfcfgibifbfcpepa

I suppose that that potential to impersonate addons is also a security concern, though.