Your size is:

{"id":1057,"date":"2018-12-09T19:42:11","date_gmt":"2018-12-09T17:42:11","guid":{"rendered":"https:\/\/2019.foss4g.org\/?page_id=1057"},"modified":"2018-12-13T17:22:31","modified_gmt":"2018-12-13T15:22:31","slug":"conference-t-shirt","status":"publish","type":"page","link":"https:\/\/2019.foss4g.org\/conference-t-shirt\/","title":{"rendered":"Conference T-shirt"},"content":{"rendered":"

<\/p>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":7,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":[],"_links":{"self":[{"href":"https:\/\/2019.foss4g.org\/wp-json\/wp\/v2\/pages\/1057"}],"collection":[{"href":"https:\/\/2019.foss4g.org\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/2019.foss4g.org\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/2019.foss4g.org\/wp-json\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"https:\/\/2019.foss4g.org\/wp-json\/wp\/v2\/comments?post=1057"}],"version-history":[{"count":11,"href":"https:\/\/2019.foss4g.org\/wp-json\/wp\/v2\/pages\/1057\/revisions"}],"predecessor-version":[{"id":1123,"href":"https:\/\/2019.foss4g.org\/wp-json\/wp\/v2\/pages\/1057\/revisions\/1123"}],"wp:attachment":[{"href":"https:\/\/2019.foss4g.org\/wp-json\/wp\/v2\/media?parent=1057"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}