At login I’m prompted to update my core to the latest firmware update "Deep update available"
When I click ‘Let’s do it now’, the menu on the left side turns blank and nothing happens.
Tried in both Firefox and Chrome to exclude a browser issue.
i tested and seems like that feature is broken somehow. Do you have particle-cli or DFU-util installed?
It’s not a showstopper for now and you can hit flash again to OTA the firmware to the core and update once that is fixed 
Thanks @kennethlimcp for checking. Will try particle-cli when I have time. Good to know its not just me 