Content type returned by WebDAV server prevents easy opening of files
A WebDAV server provides mimetypes for files as part of its directory listing to the convenience of the client. The problem is that depending on how the server is configured, it might simply just return "application/octet-stream".
On such a server, trying to open the file will make dolphin show the "Open With" dialog instead of just falling back to filename/extension based mimetype guessing.