hide empty preview column for amp-install-sw
hide empty preview column for amp-install-sw

ampproject/amp-by-example,camelburrito/amp-by-example,ampproject/amp-by-example,camelburrito/amp-by-example,camelburrito/amp-by-example,camelburrito/amp-by-example,ampproject/amp-by-example,ampproject/amp-by-example