you can stop the auto update I do not think there is a way to know what your last version was.
Click the menu button New Fx Menu and choose Options
Select the Advanced icon.
Select the Update tab.
Check Never check for updates (not recommended: security risk) and uncheck Search Engines.
https://support.mozilla.org/en-US/kb/how-stop-firefox-automatically-making-connections
I was using Firefox, closed it and opened it later like I usually do, and all of a sudden it all looked different. I checked the about button and they just updated me to 33.0. It didn't even ask me if it could upgrade! I have my settings to never check for update. I hate this new version. Thing I hate the most is that I can't manually go into Private browsing mode which goes in private on the same page, not in a new window. I hate that! Why did Firefox do this? I didn't even see anything on my screen saying "installing". I'm on Old versions of firefox, but I don't know which version I last had. Is there a way to find out a history log of versions I've had? I'm installing all kinds of different versions trying to find the right one. Headache!
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