Saving rich text/html with a wysiwyg via ajax no longer working

After I updated to 78.0.13, suddenly I am not able to save any data with html (and particularly quotes) using ajax. My CMS utilizes CKEditor 4 along with jquery and bootstrap 4. I currently host about 20 websites, most of them using this CMS. After the update, I started getting complaints that users are not able to update their sites. I looked further into it and sure enough, any content typed into the wysiwyg editor which utilizes quotes (attributes, classes, etc.) fails to go from the ajax request to the processor script. I am able to log the raw html data before it gets to ajax, but when I try to display it in the console on success, all that's displayed is the html for my entire website's homepage. The worst part: no errors in the log, the console, or on the screen. I added an error check to the ajax script but none show up. Was there some security enhancement like "magic quotes" that was brought back in this update? I'm using Php 7.2 and last I checked there isn't any sort of feature. Any thoughts?