#Drupal Core 10

I still have this issue. I see it is because for some reason Drupal is changing the ownership of the sites/default/files/js and sites/default/files/css directories back to www-data:www-data when it generates new aggregated css/js files. This is on my prod server so I need to keep aggregation enabled.

Try turning off aggregation in the settings.php file

$config['system.performance']['css']['preprocess'] = FALSE;
$config['system.performance']['js']['preprocess'] = FALSE;

Or a workaround would be to manually search and delete the .js file.