MAMP - FastCGI: comm with server "/Applications/MAMP/fcgi-bin/php7.4.12.fcgi" aborted: idle timeout (30 sec)

Go to FileEdit TemplateApachehttpd.conf

Comment out the line MAMP_FastCgiServer_MAMP

nano /Applications/MAMP/fcgi-bin/php7.4.12.fcgi

Add -idle-timeout:

exec /Applications/MAMP/bin/php/php7.4.12/bin/php-cgi -c "/Library/Application Support/appsolute/MAMP PRO/conf/php7.4.12.ini" -idle-timeout 3600

If that doesnt work, try to enable Xdebug:

PHPExtensionsXdebug (Debugger)