I finally found out, that in my specific case, images were missing dpi information and wkhtmltopdf seems to just skipped those and didn't optimize them: github.com/wkhtmltopdf/wkhtmltopdf...
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I finally found out, that in my specific case, images were missing dpi information and wkhtmltopdf seems to just skipped those and didn't optimize them: github.com/wkhtmltopdf/wkhtmltopdf...