Prevent theme from adding new copies of every uploaded image

Hi,

I use Scaffold for my blog at https://opozitie.eu and the theme is very nice. However, I don’t like the fact that it creates 2 new copies for each image I upload on every single post. I manage, resize and compress the images myself before uploading them and I don’t want any extra copy except those I allow in Media Setting.

I already found and removed this line:

add_image_size( 'scaffold-blog', 600 );

from functions.php file, but there is still another copy being created, with 768 pixels wide. And I don’t know where it comes from.

How can I prevent Scaffold to make that duplicate? What code should I edit/remove?

Thank you!

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