Changed Layouts does not save

Problem/Motivation

Layout changes do not save. I am not sure if this issue belongs in Panels or Page Manager. I first tried 8.x-1.0-alpha24, but ran into another issue ( at least I think it's a separate issue ) where I could not add content ( no button for adding content ), so I down graded to alpha23.

I discovered the issue where selecting a new layout and saving does not save the layout settings. I found this issue: https://www.drupal.org/node/2752739 which attempts to address the same problem, but the comment in https://www.drupal.org/node/2752739#comment-11506651 states that the proposed fix no longer applies. I took the commenter's recommendation and moved to 1.x-dev, but I still have the same issue.

I noticed that which ever layout I select when initially creating the variant is the one I am stuck with.

Modules installed

Relevant

• Drupal 8.1.9
• Ctools 3.0-alpha27
• Panels 3.0-beta4
• Panels IPE 3.0-beta4
• Page Manager 1.0-alpha23+14-dev
• Page Manager UI 1.0-alpha23+14-dev
• Layout Plugin 1.0-alpha22

Not sure if these are relevant

• Display Suite 2.5
• Efom 1.x-dev
• Filefield Paths 1.0-beta1
• Path Auto 1.0-alpha3
• Menu Block 1.4
• Token 1.0-beta1
• Paragraphs 1.0

Steps to reproduce

1. Create a new Page
2. select panels for Variant Type
3. In my experience, no matter what I choose for Builder, the results are the same
4. Select any layout -> Save
5. Edit the page variant, choose a new layout -> Save

It always reverts to the original layout I set for the variant. And there is always 3 log messages in this order:

Warning: call_user_func_array() expects parameter 1 to be a valid callback, class 'ds_2col' not found in Drupal\Core\Form\FormBuilder->doBuildForm() (line 979 of /var/www/dev/drupal/core/lib/Drupal/Core/Form/FormBuilder.php).

Warning: call_user_func_array() expects parameter 1 to be a valid callback, first array member is not a valid class name or object in Drupal\Core\Form\FormValidator->executeValidateHandlers() (line 83 of /var/www/dev/drupal/core/lib/Drupal/Core/Form/FormValidator.php).

Warning: call_user_func_array() expects parameter 1 to be a valid callback, first array member is not a valid class name or object in Drupal\Core\Form\FormSubmitter->executeSubmitHandlers() (line 111 of /var/www/dev/drupal/core/lib/Drupal/Core/Form/FormSubmitter.php).