Shared Collaborative editing in nextcloud

[DoS007]

In addition to #14 :

It would be really nice if you could share a link with a third person and collaborative editig a diagram. At the moment, a shared link can only download the diagram although i allowed editing using that sharelink.

?

[chrisjq]

Would be good if it could also open just for viewing also.

[nooblag]

Collaborative editing would be great. +1

[rasos]

The underlying file system needs if-match/etag header support on the file for collaborative editing #14 (comment) - but that seemed to have been deprecated.

ETag support has been implemented for the nextcloud Deck App recently stefan-niedermann/nextcloud-deck#359 - maybe this is a suitable blueprint. This Visual Studio Code extension also allows simultaneous editing with the liveshare extension https://github.com/hediet/vscode-drawio - requires to authenticate with github.

Here it is recommended to simply use the drawio embed mode #14 (comment) - is the app making use of it?