Xdebug 3.0 has updated options, so previous settings are no longer supported. We will have to update the documentation on this. Thanks for bringing that to our attention.
Only these are supported since Xdebug 3.0:
xdebug.start_with_request = trigger
xdebug.client_port = 9000
xdebug.client_host = localhost
xdebug.mode = debug
zend_extension = C:\xampp\php\ext\php_xdebug-3.0.1-7.4-vc15-x86_64.dll
Please try to change, check if phpinfo() shows xdebug as loaded and give it another shot.
The second issue is unrelated to the first one. We're going to take a look at it and get back to you as well.