Today I got an update from version 5.4.6 to version 5.4.7 on Playstore. Running Android 7.1.1. All was working perfect in 5.4.6. Once updated to 5.4.7. I had an error message about sync with Webdav (owncloud) with a private certificate - as stated in the upgrade informations - . Following the instructions I disconnected, then try to reconfigure the connection to the server. No way. I get a "folder not recognized" message. Did this 4 times. Back to 5.4.6. (Thanks to having app backup) and all good again. Try to update 3 hours later.... same thing. Back on 4.5.6. and all works fine. Any idea ?