I haven’t tested with posts. It’s directly adding via the Media library. I actually don’t need to use your plugin anymore, I just accidentally left it activated and when I couldn’t upload images starting a few days ago. I just thought it would be good to post about my experience in case any other users ran into this. I had to go through my entire list of plugins, disable one at a time, try to upload, then re-activate the plugin. I went down my entire list of plugins and I got to yours and when I deactivated it, it fixed the problem. I am running the latest Divi Theme. I’m a Sys Admin running on my own dedicated server so I have full control over all aspects of the server. It is running WHM/Cpanel on Centos 7. The Imagick PHP module is disabled. Enabling it makes no difference. WordPress will use the GD library instead automatically. No changes were made to the WordPress site when this started happening other than automatic updates of plugins and update to WordPress 5.5.3. I don’t upload images that often so trying to determine if a specific update caused the problem is virtually impossible.
These are the other plugins I have activated:
Better Search & Replace
Broken Link Checker
Divi Classic Editor
Divi-Modules – Table Maker
Duplicate Page
Easy Updates Manager
Email Address Encoder (by Till Kruss)
Formidable Forms
Formidable Forms Pro
Formidable Views
Funeral Press
Header Footer Code Manager
iThemes Security
ManageWP Worker
Popups for Divi
Smush
Sucuri Security
Ultimate FAQ
UpdraftPlus
WooCommerce
WooCommerce Catalog Visibility Options
WP Fastest Cache
WP FuneralPress Premium
Yoast SEO