	setNavButtonsState: function() {
		var $themeInstaller = $( '.theme-install-overlay' ),
			current = _.isUndefined( this.current ) ? this.model : this.current;

		// Disable previous at the zero position
		if ( 0 === this.model.collection.indexOf( current ) ) {
			$themeInstaller.find( '.previous-theme' ).addClass( 'disabled' );
		}

		// Disable next if the next model is undefined
		if ( _.isUndefined( this.model.collection.at( this.model.collection.indexOf( current ) + 1 ) ) ) {
			$themeInstaller.find( '.next-theme' ).addClass( 'disabled' );
		}
	},
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