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translated: Hello how to reduce the size of thumbnails on mobile to display multiple items per line? Thank you
i am not sure if google translator did correctly, bit confused you want to reduce thumbnail size for mobile or display more column in a row?
Currently, there is no option to reduce image size for mobile view, you can add custom CSS to resize thumbnail view.
If you want column in a row, you can use % value for grid item width like 30% will give you 3 columns in each row. please see the screenshot