"Xdebug is an extension for PHP, and provides a range of features to improve the PHP development experience. Step Debugging A way to step through your code in your IDE or editor while the script is executing."

Source: https://xdebug.org/ 

Install following the instructions from https://xdebug.org/docs/install

Note, PHP 8 settings are different than earlier versions of PHP, xdebug
For PHP 7 settings, see the prior post 
Enable PHP xdebug from the command line 

Download and place the xdebug extension in php\ext
C:\laragon8\bin\php\php-8.0.11-Win32-vs16-x64\ext

Configure your PHP 8 php.ini settings:

zend_extension=xdebug-3.0.4-8.0-vs16-x86_64

[xdebug]
xdebug.mode=debug
xdebug.start_with_request=yes
xdebug.client_host=127.0.0.1
xdebug.client_port=9081
xdebug.idekey=PHPSTORM 

Note, if you use xdebug.start_with_request=trigger, this may be more efficient for large code paths as xdebug should only be started when you send a request with XDEBUG_SESSION set, which can be set via xdebug helper for chrome or xdebug helper for firefox

You can also add arguments to your PHP call

> php -d -dxdebug.mode=debug -dxdebug.start_with_request=yes -dxdebug.client_host=127.0.0.1 -dxdebug.client_port=9081 -dxdebug.idekey=PHPSTORM your/script.php

The option -d can set/override php.ini values

-d foo[=bar]     Define INI entry foo with value 'bar'
Reference: https://www.php.net/manual/en/features.commandline.options.php


If you are using the conemu console you can add the alias to your settings -> startup -> environment

alias xphp8=C:/laragon80/bin/php/php-8.0.11-Win32-vs16-x64/php -dxdebug.mode=debug -dxdebug.start_with_request=yes -dxdebug.client_host=127.0.0.1 -dxdebug.client_port=9081 -dxdebug.idekey=PHPSTORM $*

alias php8=C:/laragon80/bin/php/php-8.0.11-Win32-vs16-x64/php $*

If you are using git for windows, which adds bash, you can add the same aliases
Edit your .bashrc
C:\Users\[youruser]\.bashrc

alias xphp8="C:/laragon80/bin/php/php-8.0.11-Win32-vs16-x64/php -dxdebug.mode=debug -dxdebug.start_with_request=yes -dxdebug.client_host=127.0.0.1 -dxdebug.client_port=9081 -dxdebug.idekey=PHPSTORM $*"

alias php8="C:/laragon80/bin/php/php-8.0.11-Win32-vs16-x64/php $*"

And use as

> xphp8 slimapp/cli.php arg1 arg2=test

Reference:Slim PHP CLI