OMG after many months of frustration I've landed on this.
This is still an issue with latest Chrome version. Sometimes the CPU usage is fairly normal but other times the CPU usage skyrockets to 100% on Xeon E3-1280 v2 and another Ryzen 7 2700X system I have. Only happens with chrome and this extension installed.
What seems to trigger it is random mouse movements over UI elements like hyperlinks/buttons etc. on the webpage. It may or may not happen sometimes but when it does it's really bad it chokes the CPU and freezes applications hard until it's done doing what it wants.
I've removed the extension since yesterday and it's not happening anymore. I believe it's due to the extension being too old and some things sure must have changed with Chrome in all this time.
I love this AV and been using since a decade but this extension either needs to be updated or removed but if kept is trouble.