gallery3540: image resize dimensions threshold it is a hidden setting so it can be changed in rails console github.com/discourse/discourse config/site_settings.yml a77759856 composer_media_optimization_image_resize_dimensions_threshold: default: 1920 hidden: true client: true but i think it needs to be added here: Hidden Site Settings Reference Guide Self-Hosting This is a reference guide for describing all available Hidden Site Settings. Required user level: Administrator Hidden site settings in Discourse are advanced configuration options that are not available through the standard admin interface. They provide additional flexibility to customize the functionality of your Discourse instance. For additional information about modifying hidden site settings, see: Enable Hidden Site Settings . Be… to change it: cd /var/discourse ./launcher enter app rails c SiteSetting.composer_media_optimization_image_resize_dimensions_threshold = 1440 exit