I was getting the warning:
Warning: Invalid DOM property 'for'. Did you mean 'htmlFor'?
I already changed to 'htmlFor' every where I used 'for'. But the warnings didn't go away.
I used VS Code to search through all files for 'for=' and all results where 'htmlFor='. So I believe everything is correct but the warning still appears.
Maybe you haven't rebuilt the code?
Did you run e.g. npm run build after the change?