Why aren't CSS files served? There is nothing in sites/default/files/css

Question

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?

Answer 1

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.