HTML Entities displaying improperly as malformed escaped code

Turns out that this specific issue was caused by someone on the IT team who wasn’t very experienced with WordPress adding some code that they found on a poorly written WordPress blog that literally starts out with an unmarked example of what not to do.

According to the IT team, this line added to wp-config.php was apparently the cause of the issue:

define( 'CUSTOM_TAGS', true );

There are two morals to this story:

  1. Always read WordPress blogs critically and verify that what you are doing is really the BEST solution, not just a solution.
  2. Never assume that others will be careful about trusting random things they read on the internet. This includes WordPress blogs.