I'm not sure this will help the developers much but it might. Under Firefox Extensions, I chose options. The first tab, General, never loads. I go to the Logs tab and the following errors are registering several times a second:
2020\5\23 10:30:03 WRN: DB set value error: InvalidStateError A mutation operation was attempted on a database that did not allow mutations.
I've attached the log, and two screenshots. One of the JavaScript errors in the General Tab, and one of the Extensions I have installed.
Evernote_Logs.txt