The Cloudflare human verification thing checks browser parameters that some extensions block or fake. Likely caused by “Canvas Blocker” if you use that. The fix is to add the specific Cloudflare subdomain this widget uses to the whitelist.

Whilst Gimp is technically powerful, you can really tell it’s made by programmers. I cannot stand the UI and shortcut defaults, but maybe I’m damaged from having used Photoshop a couple times.