Just wanna add to what's already been said:
This would be an important feature! My Obsidian vault needs a new and secure home.

If not Webdav, possibly an api or command line tool to make it easier to sync between different platforms.

Proton Bridge should support calendar, contacts, and files.

I'd love to go all in on proton, but this is also a deal breaker. I have a note taking app, Notability, that I absolutely must backup to my cloud drive. The app only supports the major clouds, onedrive, dropbox, box, etc. It also has a webdav feature but unfortunately proton not supporting it limits my ability to use protons cloud solutions.

I just paid for Proton unlimited and would love to switch to proton drive for my data needs, but this is kind of a dealbreaker for me, might need to cancel and switch back.

Yes. THIS! I would LOVE to be able to just add my Proton Drive to the "Remote" section of Dolphin on Kubuntu!

Leider ist Proton Drive eher nur eine nette spielerei. Im Bezug auf Nutzbarkeit, oder kompfort kann es bei weitem nicht mit den größeren Clouddiensten mithalten.

Die Vorschaugröße ist viel zu gering und leider wird Proton Drive auch von keiner mir bekannten App (Ausser die hauseigene) unterstüzt. Weder Scanner Apps wie GeniusScan, noch andere Sicherheitstools wie Cryptomator, Für produktiveres arbeiten wäre auch eine OCR Erkennung super. Auch ist der up und download wirklich sehr langsam und nicht mehr zeitgemäß. Werde nun wohl mein Paket komplett dowgraden, oder evtl. Proton komplett verlassen. Wichtige Dokumente werden dann eben mit Geniusscan und Cryptomator zur Googleclod wandern, dort hat man einfach keine Abstriche bezüglich Nutzbarkei- und Geschwindigkeit.

Sollte Proton es wirklich jemals hinbekommen, mit Anwendungen wie OX Drive, WebDav, Cryptomator und Geniusscan zusammen zu arbeiten, komme ich gerne wieder darauf zurück.

La messagerie OLVID nécessite une sauvegarde automatique avec WEBDAV.
C'est assez stupide de dépendre de Google Drive pour faire cette sauvegarde

ProtonDrive ne le permet pas (sauf si je me trompe )

I want to move from Evernote to Joplin but want a secure, encrypted cloud storage

het verbeteren van de bruikbaarheid van proton drive: De introductie van WebDAV-ondersteuning zou synchronisatie met populaire documentbeheertoepassingen zoals DEVONthink en Joplin mogelijk maken. Dit zou van Proton Drive een veelzijdiger hulpmiddel maken, dat een groter aantal gebruikers aantrekt.

Ich würde auch gerne meine Datenbanken von Devonthink auf dem Protondrive synchronisieren. Wäre sehr hilfreich, wenn das in absehbarer Zeit möglich wäre.

This would make it possible to sync my data across devices with other tools such as Zotero, Obsidian.

WebDAV to sync DEVONthink with Proton Drive please! Here is why:

1. Enhancing the usability of Proton Drive: Introducing WebDAV support would enable synchronisation with popular document management applications like DEVONthink. This would make Proton Drive a more versatile tool, attracting a larger number of users.

2. Expanding the user base: Many users rely on DEVONthink and other WebDAV-supported applications to organise their data. Supporting WebDAV would make Proton Drive more appealing to these users, potentially increasing subscription numbers.

3. Improving data security: Proton Mail is highly regarded for its advanced security features. Adding WebDAV to Proton Drive would allow users to securely sync data from applications like DEVONthink, further strengthening Proton Mail’s position as a leader in privacy and data security.

4. Integration with external applications: WebDAV is a widely used protocol that allows integration with various applications. Adding WebDAV support to Proton Drive would make it easier for users to collaborate with multiple document and data management tools, thereby increasing the value of Proton Drive within the software ecosystem.

5. Increasing user loyalty: Providing support for WebDAV could increase satisfaction among existing users who utilise DEVONthink and similar applications. This, in turn, could enhance user loyalty, making them more likely to continue their subscriptions to Proton Mail and Proton Drive.

Agree with comments below. Can a tech lead explain why this is not technically doable, or (hoping) perhaps it's on a roadmap and soon to be implemented?

I have a boox tablet, for reading and note-taking, and it would be nice to connect the two in a way to back-up/share my notes and books.

Wow 2 years of a company not adding a basic-*** feature that everyone needs. Might as well just delete Proton Drive.

Webdav would be very handy for syncing my Zotero library. Currently, I depend on other cloud services for this. If Proton implements Webdav in Proton Drive, I could switch completely to it, and ditch other services once and for all.

Seriously, this is the only thing stopping me from starting to pay for a plan by literally going all out on Proton Unlimited. Once they start implementing WebDAV (which is probably quite tricky due to the E2EE) I can finally have it sync with my Seedvault backups and function as a feasible personal private secure "off-site" storage solution.

I need WebDav support in order to move my KeePass database to the Proton cloud. I know, there is a KeePass plugin, which does this, but for me this is an insecure link in the chain.

Facilitates automatic backup from NAS (Synology, Qnap, etc.)