People who insist in allowing automatic installations have had issues. I tried the incremental update of 1.7 MB, and it failed in two computers, one of which did not even tell me that there was an update.
Only the complete download worked. Just do the update at your own risk.
Now, I will have to go clean up the mess done with Firefox Portable. Got it! They were at the bottom of the page, nicely hidden. And, I got, after several skirmishes, Firefox Portable.
UserAgent: Mozilla/5.0 (Windows NT 5.1; rv:6.0.1) Gecko/20100101 Firefox/6.0.1