Opening https://app.financier.io in Edge and IE11 (latest) cause the error seen here. Just stuck on the spinner. Tried flushing cookies/caches and using InPrivate browser (incognito mode) so shouldn't be caused by budget-data.
Didn't notice it before but I don't consistently test things in Edge/IE11.
I don't use it normally either but i'm on Windows 10 and its working fine for me on both.
I can log in and sync fine too.
Deleted offline files/history and it's all dandy again. Even though I had developer console set to disregard cache and always fetch from server that was obviously not enough... This is one of the reasons I don't use Edge/IE11 a lot... :-)
That's a weird one. Glad you got it fixed. :)