Which file types you can upload via the media manager popup or the fullscreen media manager is configured through the
conf/mime.conf file. It also configures the file extension ↔ mimetype association.
For security reasons it is not possible to configure DokuWiki to allow any file type.
You can find any file extension with its mime at https://filext.com/, these are used since the Igor 2022 release.
For Hogfather 2020 release and older, the icons were created with the file icon generator. Old additional icons in the old style are available at https://www.splitbrain.org/projects/file_icons