Default image sizes can be defined in WordPress under Media settings, but many theme developers add theme-specific image sizes instead of using the WordPress defaults. These custom sizes can usually be found in the functions.php file. In the Explore theme
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DesktopServer is the easiest way I have found to efficiently develop WordPress sites. I use the limited version, which allows the installation of three WordPress websites. This is enough for my purposes since I use it mainly for theme exploration
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