I wish I could say it is amazing, though. Unfortunately, I cannot. It has much room for improvements. For one thing, its UI is counterintuitive. I hit the "Add" button nothing seems to happen. I close the tab and reopen it to find out something may or may not have happened. There is no "Save" button either. Also, it is impossible to change the order of rules.

I was trying to define a rule that replace "countryOfOrigin=*&" with "&". I've had no luck so far.

По описанию именно то что надо, но увы не работает на firefox 72 (x64)
Написал правило https://yadi.sk/i/MKxk5UMIwWLrVQ но оно никак не работает.