Safari (and other webkit based browsers such as Epiphany) currently mark pages opened in a new tab as visibilityState = "prerender", when they should be "hidden" instead.
Steps to reproduce:
1) Open https://output.jsbin.com/yibobad
2) Right click on the link, and open it in a new tab
3) Wait for the new tab to load, then navigate to it
4) The page should say "hidden", but instead it says "prerender"
"prerender" visibility state has been deprecated and removed from the w3c page visibility spec (http://go/mdn/API/Document/visibilityState, https://github.com/w3c/page-visibility/issues/42). Therefore marking new tabs as "prerender" is unexpected.
Created attachment 413743 [details]
Thanks for the patch. If this patch contains new public API please make sure it follows the guidelines for new WebKit2 GTK+ API. See https://trac.webkit.org/wiki/WebKitGTK/AddingNewWebKit2API
Comment on attachment 413743 [details]
Created attachment 413749 [details]
Committed r269665: <https://trac.webkit.org/changeset/269665>
All reviewed patches have been landed. Closing bug and clearing flags on attachment 413749 [details].