Google+: Browser no longer supported

Trying to go to my Google+ account from Google's main page yields the following warning:

Your Browser is no longer supported

This is a bit annoying, since I'm using Firefox 23... Fortunately, there is an easy workaround: use your full profile link: https://plus.google.com/[profile number] and from the Profile menu on the left you will be able to access all your data.

To retrieve your profile number, once logged in go to the profile menu (top right), which should still be accessible and click on Account. On this page, find item Edit your profile. This link contains the profile number. Click on it.

P.S. Chrome 28 works just fine.

UPDATE: Everything is OK again, without any intervention on my part.