It seems that having Provider for Google Calendar and Open up Google Calendar or in conflict with each other.
While both are active, I can't verify at Google login.
It's only work if Open up Google Calendar is disabled.
The error message is:
The browser you’re using doesn’t support JavaScript, or has JavaScript turned off.
To keep your Google Account secure, try signing in on a browser that has JavaScript turned on. Learn more
I'm not sure what types of changes that add-on is doing, it appears that it is disabling javascript maybe? I don't recall touching that setting. Have you also reported this to the author of the other add-on?
It seems that having
Provider for Google Calendar
andOpen up Google Calendar
or in conflict with each other. While both are active, I can't verify at Google login.It's only work if
Open up Google Calendar
is disabled.The error message is: