This guy put down brown kitty litter, removed it, and tried WD40, TSP, and Drylock Etch, then kitty litter to absorb it. The WD40 just got it wet, the TSP worked pretty well, and then he used Drylock Etch over where he tried the WD40 and TSP, not the section he had not attempted to clean, and while he filmed himself using the first two methods, he only got video donning PPE and making stupid faces.
I had not heard of Drylock Etch and it does not seem like a complete solution:
Sweet Project Cars says to use lacquer thinner and a brass brush:
Here is a post on
Hagerty where a guy tried Dawn, Oil Vanish Stain Remover, and Bix Driveway Cleaner & Degreaser without significant effect.
Motor Biscuit summarized some of these sources, but didn't test any of them. They put less work into this than I did!
ChatGPT used 6 sources, but wrote something much shorter than Motor Biscuit. I don't know what to think!