Uncaught PHP Exception: Query tagged for node access but there is no node table, specify the base_table using meta data Can anyone give me a hint where this error could come from?

When a user tries to access a specific node in the login-area of my Drupal 8 website, he randomly gets a white screen with the message "The website encountered an unexpected error. Please try again later."

I look at the apache error logs on the server and see the following error message: 


  Uncaught PHP Exception Exception: "Query tagged for node access but there is no node table, specify the base_table using meta data." at /mywebsite.com/html_d8tst/core/modules/node/node.module line 1107, referer: http://mywebsite.com/user/251 


node.module line 1107 says: 

// Bail out if the base table is missing.
if (!$base_table) {
  throw new Exception(t('Query tagged for node access but there is no node table, specify the base_table using meta data.'));
}


I don't understand what exactly goes wrong when the error occurs. And unfortunately, I don't even see any pattern in which use cases the error occurs. 

It's only on this specific node. Sometimes it works, sometimes not. The node is of a specific content type which only logged-in users have access to. It contains several views, some of them are user-specific. 

This https://www.drupal.org/project/drupal/issues/2664748 seemed to be a similar problem, but the post was about Drupal 8.0.x-dev and was fixed. I'm working with Drupal 8.6.13  

I would be glad of any hints!
For anyone else running into this, I was able to get it to go away by checking all my blocks' permissions, especially the ones related to user information, and for me, the culprit was the User Activity Log block. Once I added the Visibility setting that only authenticated users had access to the block, the error went away.
Looks like the Drupal devs aren't having this module fail gracefully for unauthenticated users.