mastodon/app/views/shared/_og.html.haml

- thumbnail     = instance_presenter.thumbnail
- description ||= instance_presenter.description.presence || strip_tags(t('about.about_mastodon_html'))

%meta{ name: 'description', content: description }/

= opengraph 'og:site_name', t('about.hosted_on', domain: site_hostname)
= opengraph 'og:url', url_for(only_path: false)
= opengraph 'og:type', 'website'
= opengraph 'og:title', instance_presenter.title
= opengraph 'og:description', description
= opengraph 'og:image', full_asset_url(thumbnail&.file&.url(:'@1x') || asset_pack_path('media/images/preview.png', protocol: :request))
= opengraph 'og:image:width', thumbnail ? thumbnail.meta['width'] : '1200'
= opengraph 'og:image:height', thumbnail ? thumbnail.meta['height'] : '630'
= opengraph 'twitter:card', 'summary_large_image'