Is your top black color horizontal menu bar (+You, Search, Images, Maps, Play, YouTube, News, Gmail, Documents, Calendar, More) on your Google homepage suddenly gone missing?
Missing Followers
And also the list of your Followers in your Blogger blog went blank?
Yes, out of the blue the whole Follower Gadget together with your Google top menu bar cannot be seen or disappeared.
HTTPS-Everywhere Addon Conflicts With Follower Gadget And Google Menu Bar
From my own personal experience, it happened after I installed HTTPS-Everywhere addon on Firefox.From what I have read somewhere, Firefox add-ons or Extensions could conflict with the Followers Gadget and also Google menu bar.
Once I had it disabled, my Follower Gadget and Google top menu bar reappear.
Image courtesy of [David Castillo Dominici] / FreeDigitalPhotos.net