If you use Magento 2.2.x or greater and receive the error message:
1 exception(s):
Exception #0 (Magento\Framework\Config\Dom\ValidationException): Element 'block', attribute 'class': [facet 'pattern'] The value '\Magento\Framework\View\Element\Text\ListText' is not accepted by the pattern '[A-Z][_a-zA-Z\d]*(\\[A-Z][_a-zA-Z\d]*)*'.
Line: 982
Element 'block', attribute 'class': '\Magento\Framework\View\Element\Text\ListText' is not a valid value of the atomic type 'blockClassType'.
Line: 982
Exception #0 (Magento\Framework\Config\Dom\ValidationException): Element 'block', attribute 'class': [facet 'pattern'] The value '\Magento\Framework\View\Element\Text\ListText' is not accepted by the pattern '[A-Z][_a-zA-Z\d]*(\\[A-Z][_a-zA-Z\d]*)*'.
Line: 982
Element 'block', attribute 'class': '\Magento\Framework\View\Element\Text\ListText' is not a valid value of the atomic type 'blockClassType'.
Line: 982
You need to check all layout files in your theme and custom extensions, they may have a code e.g.:
If you need to extend Magento 2 Blog Module by Magefan and add a new custom text field to Blog Post edit page in Magento 2 Admin panel (Content > Blog > Posts) you must to create a simple custom Magento 2 Extension.
Videos are a great way to enrich your content since it is proved that information is perceived better by watching videos than reading a long one-piece text. Therefore you should definitely consider embedding YouTube videos to your content.
There are two ways you can insert videos in Magento 2: Default WYSIWYG Media Tool and Magento 2 YouTube Widget. Let's find out which is better analyzing their features and performance.
Default WYSIWYG Media Tool
Magento naturally has the Media Tool, which allows you to insert videos into your content.
Once you press it there appears an insert/edit media popup. In the
If you use a third-party theme for your Magento 2 store and have enabled "Use Magefan Blog Comments" as a blog comment option and flushed the Magento cache
but still cannot see the comments on the blog post page on the storefront, please compare layout file blog_post_view.xml in your theme folder
If you receive the error message "No such entity.", "No such entity with" or "No such entity with customerId" in Magento 2, the issue usually occurred when you try to load not existing object via Magento 2 Repository Class.