Tr, I think one of the outstanding features is the removal of the back button on version 10. I personally think the removal of the back button was a step in the wrong direction.
Or, it states it is in the change log. I gotta re-install firefox. Meaning, my backbutton is still there cause I updated from 9.
It is claimed to be faster, but seems 9 was about as fast to me. Whatever, but as long as it really is faster, guess its a step in the right direction.
As far as the profile, I don't know how often you update it, but if you just want to keep it the same, & install it for testing, why don't you use WinRar & create an SFX to extract it silently to %Appdata%? Assuming it is still left with the default Mozilla folder, that should be all you need.
I would imagine you can create a .bat file to copy it if your doing it from a flash drive.
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I read what you said about your wife & daughter leaving u in the dust, but I am still a little confused here. Do you mean that the x64 bit version is that much faster than the x86? On my machine, it seems pretty instant on x86, so not sure how it could be too much faster. Of course, I also have an ATI 1 GB graphics card, if that helps. And 4 GB ram (only 3.25 recognized whether 32 or 64 bit because I got the machine right at the time before 64 bit became norm. It supports 64 bit instruction sets in the processor, just that the bios doesn't support over 3.25 GB usable ram, & it has the latest bios update. So, seeing the advantage of 64 is the extra ram, I am using 32 bit now, since there is basically no difference...)
If you wanted to use a portable x86 & portable x64, you can also SFX them with winrar & use batch icon extractor to extract an exact icon clone. So your SFX portable browser will be a single EXE instead of clicking a folder, then finding the EXE, then clicking the EXE.
So you could have a folder that said Firefox: 32 Bit.exe & 64 Bit.exe
Much simpler that way. They both use the exact same profile, don't they? Or does the portable version use a profile inside the portable folder? I haven't used portable Firefox yet, so I haven't played with the features. If they do use the portable folder, why don't you just create a folder called Profiles inside the same Firefox folder & drop the profile your using inside that. Then, get the 32 & the 64 bit set to always use the same profile folder via the Firefox Profile Manager, & after you set them like that, then create the SFX after they save the settings?