Does the included FF install display pages differently?

amy

I started off running Dapper on my laptop, and I installed FF2 (Firefox 2) myself because I was anxious to use it. I've since upgraded to Edgy, and only recently started using the FF install that came with it. I discovered that all of my plugins and stuff only worked in the included FF, not my custom one.
Upon using the included FF, though, I noticed that pages are displayed a little differently than the one I installed myself. They're different in the way that they don't seem to look the way they should. Examples (they're big screenshots, so I'm not posting them in here) :

This is how my custom FF install displayed the MediaFire.com page:
from : localhost/i153.photobucket.com/albums/s...-MediaFire.png
Notice the tabs at the top are all lined up correctly.

This is how the included FF install displays the same page:
from : localhost/i153.photobucket.com/albums/s...MediaFire2.png
Notice now that the third tab is down on it's own row (and it shouldn't be).

If I hold Ctrl and use the scroll wheel on my mouse to make things smaller, this is what happens:
from : localhost/i153.photobucket.com/albums/s...MediaFire3.png
The tabs don't fit on the line correctly.

In the first screenshot, everything is displayed at a size that seems to be in-between that of the two other screenshots.

Is there a reason for this?
And, if possible, how can I fix it? It's not really critical, just annoying. Any help is appreciated

Just some more pictures, if it helps:

The photobucket page in my custom FF install:
from : localhost/i153.photobucket.com/albums/s...otobucket1.png
Everything is all lined up correctly on their own rows.

Now, that same page in the included FF:
from : localhost/i153.photobucket.com/albums/s...otobucket2.png
Things are once again messed up.

Okay, so after looking at the page's code, apparently it has something to do with the way FF is handling the CSS.

perhaps the package got another small version? some of the lesser version changes in firefox 2 got CSS modiffications .

Sorry, but I have no idea what you mean.
Are you saying that the  FF has different CSS-handling packages than the normal Mozilla one?

Those pages are different to start...in one you are logged in, in another you are not.

That said, you may have compiled Firefox 2.0, but right now on Feisty I'm running 2.0.0.4.  There have obviously been changes between these two versions...and as the above poster said, it might render differently than before.

It's so slight of a difference...