Enthusiast forms are eating URL entry

Okay, this is weird, so bear with me.

Basically, anything entered into the URL field of the join forms on my fanlistings is just disappearing. Enthusiast itself doesn't require URLs to be entered as part of the form, but I happen to run a clique using Enth in which I require URLs, and manually deny anyone who doesn't include them. Only every person who's joined for the past several months hasn't had a URL, despite the people joining absolutely putting them in.

From some testing on my end, I've filled out fake forms on this and other sites of mine powered by Enth, and all of the URLs are just disappearing. They don't show up in the join email, they're not in the database when I go to add members, etc. It's like they weren't input at all.

I strongly suspect that this started when I upgraded to your version of Enth six months ago, it's just taken me this long to realize it was happening. All other features of the script work as expected save for this.

Here's my server info:

Enthusiast: [Robotess Fork] v. 1.0.6 (Beta)
PHP: 7.3.33
MySQL: 10.3.36-MariaDB-cll-lve

I do get a warning about the mySQL version in the script, but the added fields have been working fine. My error log is 181 pages of this. Oops?

If there's any more information I can provide, I'd be happy to do so. Thanks for any help you can offer!