With the “body_class” filter you can add custom classes to your body HTML element, this can be useful when you are coding hierarchical structured CSS or you just need a specific CSS selector.
One of the most common issues regarding performance in WordPress sites is the cache, Google and GTMetrix those tools always says you need to increase your cache performance.
Sometimes we need to test specific tasks before activating our custom plugin, like identify if another plugin is already active. If you face this situation you can count with the activation hook called register_activation_hook.
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