Performance: Use scaled images instead of the full size

Hallo.

Performance Report from http://gtmetrix.com/reports/naturalnicheperfume.com/q7FKtnXh has pointed out that the NON scaled images are used instead of the proper smaller ones that are automatically generated.

This among other things give a not brilliant score of Page Speed Grade: (64%)

I am missing some setting or is something that should optimized at theme level?

Thank you Mauro

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