WordPress: Hide plugins from displaying on the WP Admin > Plugins page.

functions.php

<?php

/**
 * Hide Plugins.
 * 
 * Removes plugin(s) from displaying on the list of installed plugins on
 * the WP Admin > Plugins page.
 *
 * @param array $hidden_plugins Array of plugins to hide.
 *
 * TODO: Does the parent folder 'have' to be specified? Why or why not?
 */
add_action(
	'pre_current_active_plugins',
	function() {
		// Get global variable.
		global $wp_list_table;

		// Array of plugins to hide. Include parent folder and plugin's main file.
		$hidden_plugins = array(
			// Name of Plugin.
			'folder/file.php',
		);

		// Get all plugins that are installed.
		$installed_plugins = $wp_list_table->items;

		/**
		 * For each plugin found above, look at each one and see if there's
		 * a match in $hidden_plugins.
		 */
		foreach ( $installed_plugins as $key => $val ) {
			if ( in_array( $key, $hidden_plugins, true ) ) {
				unset( $wp_list_table->items[ $key ] );
			}
		}
	}
);