Drupal 8

If you've ever patched Drupal core with Composer you may have noticed patched files can sometimes end up in the wrong place like core/core or core/b.

The "processed" property mentioned above is what is known as a computed property on the textarea field.

While Composer isn't required when using Drupal core, many Drupal site builders use it as the preferred way of assembling websites (myself included).

In case you've had trouble tracking it down (I did), the approach to caching custom blocks is different in Drupal 8 than in Drupal 7