Must be just security/bug fixes in 57.0.3.
I've been through it with a fine tooth comb and haven't seen any changes with the possible exception of about:home has been depreciated to about:newtab.
Latest Firefox Released for Windows - Page 84 - Windows 10 Forums
The image in This post was not Photo shopped , The source links are valid-waiting may take a few days. All Browsers were updated for a reason -a security reason....
Thanks Brink....Now i should be getting it soon...probably later today...
Edit: I checked my updater and it rolled right in...running it now :)
if i look at 57.0.3 release note, it seems that ffx57 is bug free
I love the new Firefox Quantum...i was never a firefox fan but now it is my main browser...this revamped (outside and inside) version is great!
Only thing is i was having a problem with excessive memory usage and i did read that many have reported to mozilla about memory leaks so when the update came in i had my fingers crossed that perhaps they fixed that...I have been running with the update a few hours and so far so good...it has been staying down...I'll have to observe further, but looks hopeful! :)
Beta 58.0b13 came through.
Not much of an update either, only 7.2MB!
well well, FF strikes again. Today I allowed an upgrade to FF. AVG alert has just come up stating it had blocked access to bestsmileys.com as it contained URL:mal. I was going into a well used forum at that time. It told me that Firefoz contained the naughty bit.
Whats this FF Quantum, never heard of it?
Can't Photoshop the image with my cursor over it! 
