style.css doesn't refresh while Bootstrap sub-theming I followed the Drupal Bootstrap sub-theming documentation: basically copied the CDN starterkit and renamed all the files and it seems to work.
I then added a line to the empty css/style.css.

At first it didn't work except when I went to /admin/appearance/settings/ and clicked the advanced tab and set the theme to 'Bootstrap (Default)'.

I then made more modifications to the style.css, this time it didn't refresh on the pages. Checking the rendered pages I found the css file is coming as a mangled named css file.

What is involved in generated this mangled file and how to refresh after modifying css/style.css?

Can I choose a different theme from the Bootstrap settings page and still use my css modified styles?
The mangled file comes from aggregating CSS files. You will need to clear/flush the cache in order to see changes.

You can turn CSS caching off by going to /admin/config/development/performance and unchecking aggregate CSS files. Now you don't need to clear the cache to see CSS changes. 



PS: Remember to turn this back on when your website is ready for production/going live.