The solution would to return the path to the original uploaded image while providing the desired height and width so the image will be scaled by the browser using CSS scaling. This seems to be exactly how the WP core handles it when no image editing library is installed on the server.
The solution would to return the path to the original uploaded image while providing the desired height and width so the image will be scaled by the browser using CSS scaling. This seems to be exactly how the WP core handles it when no image editing library is installed on the server.
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