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This file will be placed in: /themes/default/override/layout-category.tpl (For the caterogy category entity )
N.B.: a controller is an entity type. This means that you can use this feature for the supplier, stores, product, category, and many others entities.
By entity
When you want to change the layout according to a particular entity (e.g. for the product entity with ID 1) you can define a file-layout-EntityType-ID.tpl defined as:
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