In Drupal 8, classes that are used in order to implement a content entity (which extend the ContentEntityBase class) have a validate() method that validates the values entered when creating the entity.
A similar method should be introduced in Backdrop and added to EntityInterface.
GitHub Issue #:
6061
Recent comments
OMG thank u... you are amazing.
Hiding Blocks for Small Screens
I use a similar module (Tocbot) which uses the same library, but the implementation is different. This is what I use to target the block: @media (max-width: 47.99em) { .js-toc-block.is-...
Hiding Blocks for Small Screens
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