In your sites/development.services.yml, add the following twig.config configuration nested under the parameters key:
# Local development services.
#
# To activate this feature, follow the instructions at the top of the
# 'example.settings.local.php' file.
parameters:
http.response.debug_cacheability_headers: true
twig.config:
debug: true
auto_reload: true
cache: false
services:
cache.backend.null:
class: Drupal\Core\Cache\NullBackendFactory
(Optional) Enable render caching debugging
To enable render caching debugging, update renderer.config and set its debug parameter value to true in your site's services.yml or development.services.yml.
parameters:
http.response.debug_cacheability_headers: true
twig.config:
debug: true
auto_reload: true
cache: false
renderer.config:
required_cache_contexts: ['languages:language_interface', 'theme', 'user.permissions']
auto_placeholder_conditions:
max-age: 0
contexts: ['session', 'user']
tags: []
debug: true
