A recent update to an ad block filter list now allows the uBlock Origin extension to block most of the known sites that perform port scans of your local Windows computer.
A few weeks ago, we reported that eBay is using fraud detection scripts that port scan a visitor's computer for Windows remote access programs.

uBlock Origin ad blocker now blocks port scans on most sites
A recent update to an ad block filter list now allows the uBlock Origin extension to block most of the known sites that perform port scans of your local Windows computer.