Lately, WPT results have sometimes ended up with a blank white page when I click the View HTTP/2 Dependency Graph? Example result https://www.webpagetest.org/result/211105_AiDc71_aba9d11e17260c4d13e2bb5095b273e8/3/details/#waterfall_view_step1 and the View HTTP/2 Dependency Graph link.
My Wordpress blog is behind Cloudflare but I have HTTP/3 disabled so they site is served via HTTP/2.