I have upgraded Debian on {people,talks,gtk}.php.net to Buster — solving the problem with SSL certificate issues.

I also had to upgrade PHP — it was running PHP 5.6 (now 7.3, as that comes with Debian Buster).

I also had to upgrade the globally installed PEAR packages (notably XML_Parser) as that was using PHP 4 syntax in the form of:

$x = &new …

The sites should all work now, but let me know if there are still issues with gkt.php.net, talks.php.net, or people.php.net!