When using floccus WebDAV with Apache HTTP server, you might encounter errors like the following in the default configuration.

E019: HTTP status 404. Failed PUT request. Check your server configuration and log.

Make sure to turn MultiViews off, as follows:

Alias /floccus "${HD_WEBDAV}/sync/browser/floccus/"
<Directory "${HD_WEBDAV}/sync/browser/floccus/">
  Options +FollowSymLinks -MultiViews +Indexes +Includes
  DAV On
  AuthType Basic
  AuthName "floccus"
  AuthUserFile "${HD_WEBDAV}/passwd.dav"
  Require valid-user
</Directory>

(Courtesy of https://github.com/floccusaddon/floccus/issues/824#issuecomment-968090423)