To set up attachment syncing for Zotero, register for a free Koofr account, which provides free 10G cloud storage. Once you sign into your account, navigate to user preferences and generate an app password for WebDAV. Don’t forget to copy & save it since you won’t be able to see it again on the web app.
Next, in Zotero preferences, opt to use WebDAV to sync attachments. Use https://app.koofr.net/dav/Koofr/zotero/ as the URL, and set the password field below to your Koofr app password. Click “Verify Server” to check that your password works. Make sure you repeat this process for every device you use Zotero on, since Zotero doesn’t sync the File Syncing settings across devices.
Once you finished setting sync up, your configuration should look like this:
