The images or logos of the programming languages that are shown in the presence can be edited or modified. To contribute with the images (modifying or adding) you can make a fork and then a pull request to later discuss the changes.
Notepad++ currently has support for several programming languages, scripts, etc... but this plugin only has support for some of them, so you can also contribute by adding more images, modifying the GetLanguageInfo function found in the source code file PluginDiscord.cpp and adding the respective image with JPG format in the images folder and its image project file (XCF) generated by GIMP. The image must have a resolution of 520x520 pixels