Fix the issue of Magento 2 Popup on Magento 2.1.x: Class Magento\Framework\Serialize\Serializer\Json does not exist

Issue:

I have Magento 2 Popup Version 1.1.1 and I installed as described on Magento 2.1.7.  

When I go to Marketing > Manage Pop-up I see this error:

Class Bss\Popup\Model\ResourceModel\Popup\Grid\Collection does not exist

When I click Create New Pop-up I see this big error message

1 exception(s):
Exception #0 (RuntimeException): Class Magento\Framework\Serialize\Serializer\Json does not exist

Exception #0 (RuntimeException): Class Magento\Framework\Serialize\Serializer\Json does not exist
#0 /var/www/html/vendor/magento/framework/Code/Generator/Autoloader.php(35): Magento\Framework\Code\Generator->generateClass('Bss\\Popup\\Block...')
#1 [internal function]: Magento\Framew

Solution:

The root problem is the current version (1.1.1) is not compatible with Magento 2.1.x

The class Magento\Framework\Serialize\Serializer\Json in the updated extension's version does not support Magento 2.1.x

We have fixed this issue and added these files: 

app/code/Bss/FixSerializerPopup/Block/Adminhtml/Popup/Edit/Tab/Layout.php

app/code/Bss/FixSerializerPopup/etc/adminhtml/di.xml 

app/code/Bss/FixSerializerPopup/etc/module.xml

app/code/Bss/FixSerializerPopup/registration.php

Please check and update these files to fix the issue.

For more information about our extension, please refer to Magento 2 Popup page.

If you need any further assistance, please don't hesitate to contact us at sales@bsscommerce.com 

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