Today I discovery this old feature from the Dropbox tool.
Dropbox Paper, or simply Paper, is a collaborative document-editing service developed by Dropbox. Originating from the company’s acquisition of document collaboration company Hackpad in April 2014, Dropbox Paper was officially announced in October 2015 and launched in January 2017. It offers a web application, as well as mobile apps for Android and iOS., take a look at the Wikipedia page.
You can create your own files:
To share this Dropbox file, just copy the URL from your browser.
Keep in mind, anyone with the URL may be able to edit.
Dropbox Paper: Your new collaborative workspace from Dropbox on Vimeo.