Get this addon:
https://addons.mozilla.org/de/firefox/addon/classicthemerest...
Activate the "Bottombar Toolbar" by right clicking somewhere on the top space where the bars are.
Now you have a small bar down there. Open the new funky customization menue and drag the "Statustext"-Element down there.
The only problem is that you'll find your Start-Button above the text...
Somehow I find myself installing even more Add-Ons with every major UI "improvisation" to keep a useful UI. I wish it would be the other way around where you got standard and customized from there.