The URI '/test_flipping_book_0/index.html' is invalid. You must use a valid URI scheme. dans Drupal\Core\Url::fromUri() (ligne 293 de /var/www/html/web/core/lib/Drupal/Core/Url.php).

Problem/Motivation

I've tried to add my flipping book to my site and I keep getting this message:
The URI '/test_flipping_book_0/index.html' is invalid. You must use a valid URI scheme. dans Drupal\Core\Url::fromUri() (ligne 293 de /var/www/html/web/core/lib/Drupal/Core/Url.php).

Steps to reproduce

1) Install Module
2) Try to add a Flipping Book

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes