Why aren't CSS files served? There is nothing in sites/default/files/css In my Drupal 8 installation profile, I install a theme and a lot of configuration for it.  I'm using Features to install blocks/settings/views for it, but when I enable the feature Drupal stops serving ANY CSS files on page loads.

I don't think it's an issue with features, because if I wait long enough, those files will be generated by Drupal and CSS files will load as normal, it's just that Drupal assumes those files already exist.

I have tried:
- drush cr
- clearing the cache manually in the UI
- all of the individual drush cc options
- deleting the contents of all cache_* tables and clearing the cache or drush cr
- turning aggregated css off, clearing caches, turning it back on, clearing caches
- running cron
- running /update.php

...Is there any way I can tell Drupal to generate these files instead of waiting hours for it?
A few more things to check when you have issues like this:


Any noteworthy issues on the Status page? (admin/reports/status)
Does saving the File system page generate any errors? (admin/config/media/file-system) 
This sometimes indicates permission or ownership issues in the file structure, which could keep the aggregate CSS and JS files from being generated?
Have you checked the error log for any noteworthy messages? (admin/reports/dblog)


Clearing the cache is a good place to start, but I see that you already did that. Try checking the error log immediately after clearing the cache to see if anything pops up.