Images in custom folder are not optimized

Hi,

I activated the images optimization option. It works well with all standard images, but I have a problem with custom folder images.
I have a custom plugin that set all the image imported from a desktop app as gallery images for products.
Images are available on wordpress media manager too, but they are not optimized.
Original files are stored in mydomain.ext/wp-content/uploads/custom-folder/custom-subfolder/filename.jpg.

How I can fix it or force the plugin to optimeze these images?

Thank you

• This topic was modified 3 years, 2 months ago by bulder87.