I have been running a Drupal 8 site with Pixture Reloaded theme, based on Adaptive theme (in my .info file, the corresponding lines are:
'base theme': at_core
'subtheme type': adaptive_subtheme)
and suddenly, without having done any changes in the site code (just entered content), I get errors of type:
The website encountered an unexpected error. Please try again later.
Twig_Error_Loader: Template "themes/adaptivetheme/at_core/templates/layout/html.html.twig" is not defined (Drupal\Core\Template\Loader\ThemeRegistryLoader: Unable to find template "themes/adaptivetheme/at_core/templates/layout/html.html.twig" in the Drupal theme registry.). in Twig_Loader_Chain->getCacheKey() (line 115 of vendor/twig/twig/lib/Twig/Loader/Chain.php).
Also, I get similar error when trying to login in the admin, so I cannot clear any cache (if this could help). The site was working the same day earlier and the only thing I have done is enter new content (after having created a new view).
I would appreciate any help.