If a page pops up stating this on an Orange Backround
 
DO NOT DO NOT click on it
 
this is NOT an official FF upgrade it is a trojan/virus nasty thing
 
FF updates automatically

Actually I have FF set to notify me of (but not install/download) updates.
 
When this happens it's just a little, innocuous "toast" style popup in the lower right corner of the program saying "Firefox Version X.X is available" or something like that.
 
I would certainly be wary of a big bold popup. Good to know though.
 
I will recommend that you add AdBlock+ and Noscript to your FF addons. Most of that crap worms it's way in through ads and whatnot. Those two addons have helped keep pretty much all of that type of gack away for almost a decade now. I don't think I've ever gotten a legit positive virus/malware/etc detection since I've been using them (touch wood... which is what "she" said... or so I've heard).
 
Anyhoo... good heads up...
 
and don't forget to put on yer internet rubbers, lads.

Doodz! Doodz! DOODZ!!!
 
I totes getzit!!!
 
It's funnay becuz TROJAN is like a latex condome* brand!!!11
 
Just like the we call those high fallutin' doodz around here "BAKERS" becuz...
 
...
 
...nevermind.
 
 
 
 
 
 
*i shure wish i lived in one of those

Beepster
It's funnay becuz TROJAN is like a latex condome* brand!!!11
*i shure wish i lived in one of those

Here ya go!

Wasn't it a condom joke that got the Smothers Brothers kicked off the air?
 
 
 
alt+prntscrn

Beepster
Wasn't it a condom joke that got the Smothers Brothers kicked off the air?
 
 
 
alt+prntscrn

Nah, they talked about Pro Tools.

How does the Trojan manifest itself?
 
Firefox updated itself and I don't know if it was the real update or this trojan.
 
I'm getting sections of screens stretched out over pages.
 
AVG and Malware bytes have both come up clean
 

Kamikaze
How does the Trojan manifest itself?
 
Firefox updated itself and I don't know if it was the real update or this trojan.
 
I'm getting sections of screens stretched out over pages.
 
AVG and Malware bytes have both come up clean
 

 
read this
 
 
 

 

It's not really answering  my question. It's talking about the warning you not to do the update because its a Trojan, not what happens if you do do the update. What happens then.
 
I saw Firefox was updating itself, at the weekend and since then, it's been a bit funky with lines of a screen stretching across pages. Maybe it was a proper update, but is buggy, maybe it was trojan and the symptoms. Perfect timing, This is what is happening.