I finally got a chance to fix the user registration. I just made use of the Network Subsite User Registration plugin. There are other posts about making the modifications yourself but this worked and makes things simpler. There was also an issue with the WordPress mailer on Debian. Turns out WordPress uses a modified version of phpmailer that was interfering with Debian supplied (and required) package libphp-phpmailer. Here’s the fix:

*** class.phpmailer.php.orig    2018-12-01 14:09:47.000000000 +0000
--- class.phpmailer.php    2020-01-01 22:00:47.817057652 +0000
***************
*** 1492,1497 ****
--- 1492,1498 ----
      public function getSMTPInstance()
      {
          if (!is_object($this->smtp)) {
+             require_once( 'class.smtp...

TL;DR: To support server deployment automation, the WordPress front end has been merged together with other OW sites. Unfortunately, this breaks user registration until the package maintainers fix it. I’ll have to look into a fix another day. I’m really busy these days. Existing accounts should work as usual. Please report anything else that’s broken.

Previously, the WoW site was a stand alone WordPress site served at its URL by the web server under the same domain. Now, it’s just another site that’s part of the Obsidian Worlds multi-site deployment. This required merging the stand-alone site and multi-site databases. I’m documenting the process here for prosperity since the bulk of my time was spent hunting down the information...

The server has been updated again. This update finally corrects the very annoying stuck disconnect bug. Let us know if there are any other issues. Please report issues to [email protected]