Secure view or ‘Hide download’: Prevent your shared files from getting downloaded

When sharing a public link to a third party to view material on your Nextcloud there is a ‘Hide download’ option available to check. When ‘Hide download’ is enabled, PDF documents and images will appear on the viewers screen without the menu options to download the file(s) or add them to their own private cloud.

Note that this feature will prevent most normal users from downloading the content but keep in mind how the web works: If you can see something on it – it is there and it can be copied by users with more technical skills. Secure view restricts the ability to download the file but this can be worked around with screenshots and browser tricks. Moreover, it has to be supported by Nextcloud apps, and most don’t support this yet. Think of the PDF viewer, gallery app and so on. Collabora and ONLYOFFICE have both implemented support for this, however, see below.

Collabora provides a way to watermark the documents with a configurable text, font and other properties. This feature is integrated in Nextcloud so you can configure Collabora to block copying of text, printing and downloading when hide download is enabled, while the view is watermarked.When ‘Hide download’ is enabled, even screenshots of shared documents will be marked with a preconfigured watermark showing the name of the user who shared the file, the IP address of the person who opens it or showing the date and time at which the document was opened.

Users can still edit documents, if edit rights are given, providing a great way of keeping documents secure while still providing limited access! When needed, Collabora can be configured to open PDF documents and images, applying these security features to all documents on the server.