The current list of authorized file extensions allowed for upload are:
jpg, jpeg, png, gif, heic, heif, webp
EDIT: just added webp as well.
For text, it’s better to copy and paste short text bits here using formatted text. For longer outputs, it’s best to use a pastebin service or create a gist and link it here.
Compressed archives will never be allowed for the reason @Strit mentioned above.