Install Magento 2.2.4 on Windows Localhost Using XAMPP

0) Verify, Are content of js/css files is cached in a browser?

1) Install xdebug and try to debug pub/static.php

2) I am using www-data groups and magento user and 777 for static files.

3) see 2). Do not use root to run static files deploy and do not run it in developer mode. Also, you need clean pub/static folder after setup:static-content:deploy running, because its break automatic redeploy.

4) It looks right

Try fix permissons by commands below

sudo find var vendor pub/static pub/media app/etc -type f -exec chmod g+w {} \; && sudo find var vendor pub/static pub/media app/etc -type d -exec chmod g+ws {} \; && sudo chown -R $USER:www-data . && sudo chmod u+x bin/magento
sudo find var pub/media pub/static -type d -exec chmod g+ws {} \;
sudo find var pub/media pub/static -type f -not -name .htaccess -exec chmod g+w {} \;
sudo find -L vendor/bin -type f -exec chmod u+x {} \;