Viewing public files now requires 'access content' permissions

In order to support File entities in Drupal's REST system in a secure way, starting in Drupal 8.5, file entities in the public file system will only be viewable with the "access content" permission (which recently moved to a system-wide permission; see The 'access content' permission is always available). Downloads permissions remain unaffected.

In practice, this should hopefully have very little impact, since most sites using the public file system also would allow users to view content on the site.

However, if your modules are experiencing any test failures, test users may need to be updated to include this permission, e.g.:

-    $this->webUser = $this->drupalCreateUser(['view test entity', 'administer entity_test content']);
+    $this->webUser = $this->drupalCreateUser(['view test entity', 'administer entity_test content', 'access content']);