Try Japanese business banking - where you have to pick an OS and stick with it when registering (with a paper form), and must use either the ESR release of Firefox or Internet Explorer. If you don't have a user agent of either of those it won't even let you sign in.
Always spoof your user agent string, for firefox the setting is general.useragent.override
Maybe now, not really sure if there are now changes (hopefully, since Microsoft is dropping IE), but in a time where browser plugins are abound you can't place an ActiveX plugin inside Firefox (or vice versa).