I want to stop generate thumbnail, how can I do

[cdub]

For v4 you can do the following. (I coudn’t find a better way to disable thumbnail generation)

Create the following file and restart the server:
src\extensions\upload\strapi-server.js

module.exports = (plugin) => {
    var imageManipulation = plugin.services['image-manipulation'];
    plugin.services['image-manipulation'] = () => {
        return {
            ...imageManipulation(),
            generateThumbnail: () => { }
        };
    };
    return plugin;
};