最新の管理/アップグレード後、管理ダッシュボードが読み込まれない

Looking into my browser console:

content.js:150 Error: Cannot set user agent for iframe with location different to this page

and

error in _ember_jquery-27e777857b8c0730dacfe09cb11711365d21a5db4f9ee0b85d494e4259cf6cda.js:9861

Uncaught TypeError: e.indexOf is not a function
    at we.fn.init.we.fn.load (_ember_jquery-27e777857b8c0730dacfe09cb11711365d21a5db4f9ee0b85d494e4259cf6cda.js:9861)
    at window.jsonFeed (b9a6ce49-e39b-4ac1-b776-b740bd27ba7b.js:6)
    at geolocation.onetrust.com/cookieconsentpub/v1/geo/countries/EU?callback=jQuery33109029024044289335_1540209825048&_=1540209825049:1

a number of Failed to load resource: net::ERR_BLOCKED_BY_CLIENT for google analytics, twitter, facebook, etc.

and a number of errors for /whos-online

MESSAGE BUS FAIL: callback /whos-online caused exception s.user.get is not a function

then these:

admin/dashboard/general.json?_=1540209825052:1 Failed to load resource: the server responded with a status of 502 (Bad Gateway)

general.json:1 Failed to load resource: the server responded with a status of 502 (Bad Gateway)

I see this thread:

https://meta.discourse.org/t/latest-update-breaks-admin-dashboard/30987

which suggests a bad upgrade or incompatible plugin… no plugins added / changed between the last time things worked and the /admin/upgrade - so potential bad upgrade? I didn’t receive any errors either when rebuilding or the upgrade, so unsure what to do at this point?