Alternative to Google Docs with similar feature set

Question

I'm looking to offer people an alternative to using Google Docs (and to use it myself). I'm not constraining myself to a specific use case, like this question - I'm interested in a general alternative with a similar feature set.

What are the differences, though?

Required:

• All "basic" features of Google Docs, except perhaps for storage of images/media. I won't spell out a long list of strictly necessary basic editing, made a reasonable judgement yourselves.
• You're not actively spied upon (e.g. in the sense of Google and the NSA) - not because I'm interested in doing secretive work, just on principle and for not feeling exploited like that.
• Responsive, without noticeable lag, when one person is editing, even with 5-6 other people looking at the document
• Does not communicate with large social networks or other corporate systems in order to do its job.

Desired:

• Responsive, without noticeable lag, even when 5-6 people are editing simultaneously
• No need to create an account in order to edit when invited or having the link, e.g. you can just use an arbitrary nickname with no authentication that you're the same person as before. There could be authenticated users, but that should be an option, not mandatory.
• The code behind the service is libre-licensed
• You can theoretically self-host
• Support for Right-To-Left content (including setting paragraph direction - which is not the same thing as the alignment).
• Operated by non-commercial entity.
• No ads.

Answer 1

Cryptpad might be something for you. It has a special focus on privacy:

CryptPad is a private-by-design alternative to popular office tools and cloud services. All the content stored on CryptPad is encrypted before being sent, which means nobody can access your data unless you give them the keys (not even us).

It offers most of the usual office-type apps in a browser:

• word processor
• presentation
• spreadsheet
• poll
• code editor
• Kanban board
• shared whiteboard
• CryptDrive for online storage

It can be used with or without an account, and is anonymous (except for the email address required for signup). All data is encrypted in the browser. Sharing with others is possible, by simply sharing a link (which includes the encryption key in the URL). Concurrent editing works well (though I did not use it extensively).

It is free software (GNU Affero GPL), and available on GitHub: https://github.com/xwiki-labs/cryptpad . Self-hosting is possible, and documented.

It is mainly intended for online editing, but documents can be downloaded or exported to PDF.

If you choose to use the version hosted by the developers, you can use it free of charge, with 1 GB of online storage. There are paid plans available for 5-25€/month, which increase the storage available.

Answer 2

Check out the Nextcloud ecosystem. They offer an in-browser editing feature called Collabora. This software has been forked from the Libreoffice Suite. You can self-host this, and it is free.

In theory, joint editing the same online-document works, at least if edited sequentially. That is, when Document is edited remotely, in-browser, but only by one person at a time.

But in practice but ithe Collabora Tools are slow at times, and in some documents, e.g. presentation slides with complex layout, the formatting might bite the dust.

So me and my colleagues avoid in-browser editing. They prefer downloading and uploading again.

But over the last cuple of years the IT admins at our institute now prefer to host Nextcloud rather than Owncloud or Powerfolder.

Edit: Nextcloud has already been mentioned in the question you've linked to but never mind. You cannot really expect people to click on that link first.