No UI after upgrade

Prerequisites

Volumio Information

PRETTY_NAME=“Raspbian GNU/Linux 8 (jessie)”
NAME=“Raspbian GNU/Linux”
VERSION_ID=“8”
VERSION=“8 (jessie)”
ID=raspbian
ID_LIKE=debian
HOME_URL=“http://www.raspbian.org/
SUPPORT_URL=“http://www.raspbian.org/RaspbianForums
BUG_REPORT_URL=“http://www.raspbian.org/RaspbianBugs
VOLUMIO_BUILD_VERSION=“b9cd485c2d7861a79d18f42ff0fdb052338b2239”
VOLUMIO_FE_VERSION=“2932a2aa65665ab9ec21cd0bdf3d21669bbbf643”
VOLUMIO_BE_VERSION=“8583c814bdc88e8c28c10464bec8226bce2b0634”
VOLUMIO_ARCH=“arm”
VOLUMIO_VARIANT=“volumio”
VOLUMIO_TEST=“FALSE”
VOLUMIO_BUILD_DATE=“Mon May 25 18:53:02 CEST 2020”

VOLUMIO_VERSION=“2.777”
VOLUMIO_HARDWARE=“pi”
VOLUMIO_HASH=“c75975235b22f56393d7c4516aa10590”

–>
Volumio Version: 2.777
Hardware: pi
DAC: Hifiberry DAC+DSP

Debug Log

Steps to Reproduce

  1. Upgraded Volumio from March 25(??) release to to current 2.777 release using webui
  2. upgrade successful, reboot no UI for contemporary , just a blank screen
  3. run gulp serve --theme=“volumio” ( which luckily I had) , found later I can do the same via Myvolumio.org
  4. set UI to Classic, it works but contemporary now always give blank screen
  5. Ran volumio pull still same issue

Any ideas how to get back to Contemporary UI which I prefer over Classic? which a fresh install, which is pain to do as I have to install Python 3.6 + lot of other stuff to get the DSP part working on the DAC

IMHO it does not show because you probably did some custom coding on Volumio or the UI part.
To undo your chances you can do

volumio updater restorevolumio

Thank you very much, that solved the problem