Found the issue. This update includes a composer autoloader used to load the GeoIp2\Database\Reader class from the plugin directory.
My project already had a composer autoloader so Wordfence’s one got obscured or something. I just recreated the the autoloader from my project using composer commands (I have not done that in years) and they worked fine together again. This is a very project specific issue, so YMMV.
Today I was advised that a site I manage was down.
I have multiple log lines with this error
[Wed Sep 12 19:49:02 2018] [warn] [client 82.13.40.155] mod_fcgid: stderr: PHP Fatal error: Class ‘GeoIp2\\Database\\Reader’ not found in /home/xxx/news/wp-content/plugins/wordfence/models/common/wfGeoIP2.php on line 28
I disabled the wordfence plugin and the site was up again.
