Upload of other files than images not possible

Even shown in the demo docs, it announces, that editor.js is running beneath codex.docs which is capable of handling attachments other than pictures (https://docs-demo.codex.so/codex-docs). Unfortunately it seems like codex.docs is not able to do so. Can this be added as well as the possiblity to add other plugins (maybe there might be one to have colored text :))